Methods, Systems, and Devices for Message Destination Hunting

ABSTRACT

Methods, servers and systems for communicating signaling information in a telecommunications signaling network implement methods that include receiving a first message encoding signaling information from a source component and processing the message using a fixed pipeline having a plurality of modules, each module having at least one procedure for performing a specific set of tasks. Application level routing operations may be performed to identify a suitable destination component. Information contained in the first message may be used to generate a second message encoding signaling information, which is sent to the identified destination component.

RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.14/568,249, titled “Methods, Systems and Devices for DynamicallyModifying Routed Messages” filed on Dec. 12, 2014, which is acontinuation of U.S. application Ser. No. 13/309,221 filed on Dec. 1,2011, which claims the benefit of priority to U.S. ProvisionalApplication No. 61/423,986, titled “Dynamic Connector Router” filed Dec.16, 2010 and U.S. Provisional Application No. 61/494,300, entitled“Methods, Systems and Devices for Dynamic Context-Based Routing” filedJun. 7, 2011, the entire contents of all of which are herebyincorporated by reference.

BACKGROUND

Wireless and cellular communication technologies have seen dramaticimprovements over the past few years. Cellular service providers nowoffer users a wide array of services, higher usage limits and attractivesubscription plans. Wireless dongles and embedded wireless modem cardsallow users to use tablet computers, netbooks and laptops to accesswireless Internet protocol (IP) and data services through the cellularnetworks. Internet-enabled smart phones, tablets and gaming consoleshave become essential personal accessories, connecting users to friends,work, leisure activities and entertainment. Users now have more choicesand expect to have access to content, data and communications at anytime, in any place. As more users utilize these services,telecommunication system operator networks must expand to meet theincrease in user demand, support the array of new services and providefast, reliable communications. This expansion has greatly increased thecomplexity of wireless and cellular networks, and the efficient routingand management of signaling traffic is becoming an ever more challengingtask.

SUMMARY

The various embodiments provide methods, devices and systems forenabling communications between multiple instances of components in atelecommunications network. The various embodiments provide protocolagnostic interfaces that allow communications between source anddestination nodes in a telecommunication system operator network.Routing and load-balancing decisions may be made dynamically based on acontext and content of the information being communicated. Messagesbeing communicated may be opened and the information contained thereinused to make intelligent connection management and control/rules routingdecisions. Calls may be made to external systems requesting additionalinformation for a specific message being communicated. Information fromexternal systems may be used to modify the contents of the informationbeing communicated or to aid in routing and/or load balancing operationswithin the operator's network. Information specific to a particularnetwork node, protocol, application, message or message type may bestored in an internal memory and referenced for future routing and/orload balancing operations. Routing and load balancing algorithms may beupdated as internal/external data changes.

The various embodiments include methods of communicating signalinginformation in a telecommunications signaling network that may includereceiving, in a first processor, a first message encoding signalinginformation from a source component, decoding the received first messageinto an internal representation of the message, processing the internalrepresentation of the message via a pipeline having a plurality ofstages, in which each stage may contain one or more procedures forperforming a specific set of tasks, performing application level routingoperations using contextual information derived from the internalrepresentation to identify a destination component, encoding thesignaling information contained in the internal representation into asecond message, and sending the second message encoding the signalinginformation to the identified destination component. In an embodiment,performing application level routing operations using contextualinformation derived from the internal representation to identify adestination component includes using at least one pipeline stage to makea routing decision using a discrete number of configurable procedures.In a further embodiment, the pipeline type is one of a request handlerpipeline, a response handler pipeline, a failover handler pipeline, or aredirect handler pipeline. In a further embodiment, the pipeline typeand instance is selected on a per message type or on a per applicationbasis. In a further embodiment, the pipeline may have a plurality ofstages that include at least one stage from the group consisting of arealm routing lookup stage, a session lookup stage, a gather data stage,a routing core stage, a prepare AVS stage, a filter stage, a dispatcherstage, a session update stage, and a redirect stage.

Further embodiments include a server configured with server-executableinstructions to perform operations that may include receiving a firstmessage encoding signaling information from a source component, decodingthe received first message into an internal representation of themessage, processing the internal representation of the message via apipeline having a plurality of stages, in which each stage may containone or more procedures for performing a specific set of tasks,performing application level routing operations using contextualinformation derived from the internal representation to identify adestination component, encoding the signaling information contained inthe internal representation into a second message, and sending thesecond message encoding the signaling information to the identifieddestination component. In an embodiment, the processor may be configuredwith processor-executable instructions to perform operations such thatperforming application level routing operations using contextualinformation derived from the internal representation to identify adestination component includes using at least one pipeline stage to makea routing decision using a discrete number of configurable procedures.In a further embodiment, the processor may be configured withprocessor-executable instructions to perform operations such that thepipeline type is one of a request handler pipeline, a response handlerpipeline, a failover handler pipeline, or a redirect handler pipeline.In a further embodiment, the processor may be configured withprocessor-executable instructions to perform operations such that thepipeline type and instance is selected on a per message type or on a perapplication basis. In a further embodiment, the pipeline may feature aplurality of stages that include at least one stage from the groupconsisting of a realm routing lookup stage, a session lookup stage, agather data stage, a routing core stage, a prepare AVS stage, a filterstage, a dispatcher stage, a session update stage, and a redirect stage.

Further embodiments include a non-transitory server-readable storagemedium having stored thereon server-executable instructions configuredto cause a server to perform operations that may include receiving afirst message encoding signaling information from a source component,decoding the received first message into an internal representation ofthe message, processing the internal representation of the message via apipeline having a plurality of stages, in which each stage may containone or more procedures for performing a specific set of tasks,performing application level routing operations using contextualinformation derived from the internal representation to identify adestination component, encoding the signaling information contained inthe internal representation into a second message, and sending thesecond message encoding the signaling information to the identifieddestination component. In an embodiment, the stored server-executableinstructions may be configured to cause a server to perform operationssuch that performing application level routing operations usingcontextual information derived from the internal representation toidentify a destination component includes using at least one pipelinestage to make a routing decision using a discrete number of configurableprocedures. In a further embodiment, the stored server-executableinstructions may be configured to cause a server to perform operationssuch that the pipeline type is one of a request handler pipeline, aresponse handler pipeline, a failover handler pipeline, or a redirecthandler pipeline. In a further embodiment, the stored server-executableinstructions may be configured to cause a server to perform operationssuch that the pipeline type and instance is selected on a per messagetype or on a per application basis. In a further embodiment, the storedserver-executable instructions may be configured to cause a server toperform operations such that the pipeline has a plurality of stages thatinclude at least one stage from the group consisting of a realm routinglookup stage, a session lookup stage, a gather data stage, a routingcore stage, a prepare AVS stage, a filter stage, a dispatcher stage, asession update stage, and a redirect stage.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated herein and constitutepart of this specification, illustrate exemplary aspects of theinvention, and, together with the general description given above andthe detailed description given below, serve to explain features of theinvention.

FIG. 1 is a communication system block diagram illustrating networkcomponents of a communication system having an evolved packet core (EPC)architecture suitable for use in the various embodiments.

FIG. 2 is a communication system block diagram illustrating networkcomponents of an example communication-system having a policy andcharging control (PCC) network in accordance with the variousembodiments.

FIG. 3 is a network architectural diagram illustrating logicalcomponents and information flows in an example policy and chargingcontrol network.

FIG. 4 is a network architectural diagram illustrating logicalcomponents and communication protocols in an example policy and chargingcontrol network.

FIG. 5 is an illustration of an example message structure forcommunicating signaling information suitable for use with an embodiment.

FIG. 6 is a network architectural diagram illustrating an expandedpolicy and charging control network having multiple instances of thesame logical components.

FIG. 7A is a network architectural diagram illustrating an expandedpolicy and charging control network that includes a Diameter routingagent (DRA).

FIG. 7B is an architectural diagram illustrating an expanded policy andcharging control network that includes a dynamic context router (DCR) inaccordance with various embodiments.

FIG. 8 is a component block diagram illustrating the logical componentsand communication links of an example dynamic context router system inaccordance with various embodiments.

FIG. 9 is an architectural diagram illustrating example signaling andmessage flows in a network that includes a dynamic context router systemin accordance with the various embodiments.

FIG. 10A is a process flow diagram illustrating an embodiment dynamiccontext router method for receiving, processing and transmittingsignaling messages in accordance with various embodiments.

FIG. 10B is a process flow diagram illustrating an embodiment dynamiccontext router method for determining if a specific instance of adestination node is required to perform load balancing and contextrouting operations in accordance with various embodiments.

FIG. 11 is an architectural diagram illustrating example logicalcomponents and information flows of an example dynamic context routersystem in accordance with an embodiment.

FIG. 12 is an illustration of an example dynamic context router topologytree that may be used for performing routing and load balancingoperations by hierarchy in accordance with various embodiments.

FIG. 13 is a process flow diagram illustrating an embodiment dynamiccontext router method for processing Diameter messages in accordancewith various embodiments.

FIG. 14 is a process flow diagram illustrating an embodiment dynamiccontext router method for performing hunting operations in accordancewith various embodiments.

FIGS. 15A-17C are network architectural diagrams illustrating logicalcomponents and information flows of example dynamic context routersystems configured to perform failover operations in accordance withvarious embodiments.

FIG. 18 is a network architectural diagram illustrating example logicalcomponents and information flows of an example dynamic context routersystem configured to perform fork routing operations.

FIG. 19 is a process flow diagram illustrating an embodiment dynamiccontext router method for performing fork routing operations inaccordance with various embodiments.

FIG. 20 is a component block diagram illustrating the logical componentsand interfaces of an example dynamic context router system in accordancewith the various embodiments.

FIG. 21 is an illustration of an example request message processingpipeline in a dynamic context router system.

FIG. 22 is an illustration of an example response message processingpipeline in a dynamic context router system.

FIG. 23 is an illustration of an example failover message processingpipeline in a dynamic context router system.

FIG. 24 is an illustration of an example message redirect processingpipeline in a dynamic context router system.

FIG. 25 is a component block diagram of a server suitable for use withan embodiment.

DETAILED DESCRIPTION

The various embodiments will be described in detail with reference tothe accompanying drawings. Wherever possible, the same reference numberswill be used throughout the drawings to refer to the same or like parts.References made to particular examples and implementations are forillustrative purposes, and are not intended to limit the scope of theinvention or the claims.

The word “exemplary” is used herein to mean “serving as an example,instance, or illustration.” Any implementation described herein as“exemplary” is not necessarily to be construed as preferred oradvantageous over other implementations.

The terms “mobile device,” “wireless device” and “user equipment (UE)”may be used interchangeably and refer to any one of various cellulartelephones, smart-phones (e.g., iPhone®), personal data assistants(PDA's), palm-top computers, tablet computers, laptop computers,wireless electronic mail receivers (e.g., Blackberry®), VoIP phones,wire-line devices, devices implementing Machine-to-Machine (M2M)technologies, multimedia/Internet enabled cellular telephones, andsimilar electronic devices capable of sending and receiving wirelesscommunication signals. A wireless device may include a programmableprocessor and memory. In a preferred embodiment, the wireless device isa cellular handheld device (e.g., a mobile device), which cancommunicate via a cellular telephone communications network.

The phrases “Diameter reference points,” “Diameter applications,” and“Diameter interfaces” may be used interchangeably and refer to specificimplementations of the Diameter protocol. However, when possible, thephrase “Diameter application” is used to describe an extension of theDiameter base protocol (which is built on top of the Diameter baseprotocol) and the phrase “Diameter reference point” is used to describean interface between network components that employ the Diameterprotocol to realize communications (i.e., network components realizecommunications over a reference point). Diameter applications may usethe same name as Diameter reference points (e.g., Gx reference point andGx Diameter application), the distinction being that at each end of thereference point there may be a client node and a server node.

As used herein, the word “domain” refers to a logical entity configuredentirely within the DCR system that can be used to represent any routingdestination based on a scenario. It should be understood that thedomains discussed herein differ from, and provide functionality over andabove those provided by, the domain-like concepts present in theDiameter protocol standard. Examples include the “Destination-Realm” and“Destination-Host” attribute-value-pairs (AVPs).

The term “attribute value stream” and its acronym “AVS” are used hereinto refer to a message structure that stores information corresponding toinformation carried by a telecommunications network message (e.g., aDiameter message). Each AVS may include one or more structured fields(e.g., a session identification field, a policy and charging rulesfunction identification field, a domain field, an origin-host field, asubscriber identification field, an address field, etc.), and may beused by a dynamic context router (DCR) system as internal representationof a telecommunications network message (e.g., a Diameter message).

A number of different cellular and mobile communication services andstandards are available or contemplated in the future, all of which mayimplement and benefit from the various embodiments. Such services andstandards include, e.g., third generation partnership project (3GPP),long term evolution (LTE) systems, third generation wireless mobilecommunication technology (3G), fourth generation wireless mobilecommunication technology (4G), global system for mobile communications(GSM), universal mobile telecommunications system (UMTS), 3GSM, generalpacket radio service (GPRS), code division multiple access (CDMA)systems (e.g., cdmaOne, CDMA2000™), enhanced data rates for GSMevolution (EDGE), advanced mobile phone system (AMPS), digital AMPS(IS-136/TDMA), evolution-data optimized (EVDO), digital enhancedcordless telecommunications (DECT), Worldwide Interoperability forMicrowave Access (WiMAX), wireless local area network (WLAN), Wi-FiProtected Access I & II (WPA, WPA2), and integrated digital enhancednetwork (iden). Each of these technologies involves, for example, thetransmission and reception of signaling and content messages. It shouldbe understood that any references to terminology and/or technicaldetails related to an individual standard or technology are forillustrative purposes only, and are not intended to limit the scope ofthe claims to a particular communication system or technology unlessspecifically recited in the claim language.

The various embodiments provide methods, devices and systems formanaging communications in a network. The various embodiments provide adynamic context router (DCR) that operates as a flexible, protocolagnostic, application-level router and load balancer. The dynamiccontext router may perform message routing, relay, and redirectoperations. The dynamic context router may identify communicationpartners and/or determine resource availability. The dynamic contextrouter may make routing and load-balancing decisions dynamically basedon the context and content of the information being communicated. Thedynamic context router may look inside the messages being communicatedand make intelligent decisions based on the content of the messages. Thedynamic context router may make calls to external systems requestingadditional information for a specific message being communicated. Thedynamic context router may request information from external systems anduse the information to modify the contents of the information beingcommunicated or to aid in the routing and/or load balancing operations.The dynamic context router may store information specific to aparticular network node, protocol, application, message or message typein an internal memory and reference the internal memories whenprocessing future communications related to that node, protocol,application, message or message type. The dynamic context router mayupdate its routing and load balancing algorithms as internal/externaldata changes.

In an embodiment, the dynamic context router may provide pipelining,topology hunting, and/or message forking operations.

In an embodiment, the dynamic context router may access subscriberinformation stored in subscriber profile repositories (SPRs) and use thesubscriber information to aid its routing and load balancing operations.In an embodiment, the dynamic context router may modify the contents ofthe messages being communicated with subscriber information retrievedfrom a subscriber profile repository. In an embodiment, the dynamiccontext router may access online charging systems (OCSs) or off-linechanging systems (OFCSs), and use charging and/or billing informationfrom those systems to aid its routing and load balancing operationsand/or to modify the contents of the messages being communicated. In anembodiment, the dynamic context router may access additional businesssupport systems (BSS)/operations support systems (OSS) to aid itsrouting and load balancing operations and/or to modify the contents ofthe messages being communicated.

In an embodiment, the dynamic context router (DCR) may generate, procureand/or use a topology tree, referred to herein as a “DCR topology tree.”The DCR topology tree may be used to efficiently identify and locatenodes in the network. In an embodiment, the dynamic context router mayuse the DCR topology tree to perform routing and load balancingoperations by hierarchy.

In an embodiment, the dynamic context router may perform messagedestination hunting operations to identify a correct instance of adestination node that cannot otherwise be ascertained from informationincluded within the message or otherwise available. In an embodiment,the dynamic context router may use the DCR topology tree to performinghunting operations by hierarchy.

In an embodiment, the dynamic context router may communicate with adictionary to receive decoding rules that can be used for decodingmessage types with which the dynamic context router is unfamiliar. In anaspect, the dictionaries may be implemented as databases, and thedictionary databases may be internal to the dynamic context router orexternal to the dynamic context router (e.g., may exist on dictionaryservers). In an embodiment, the external dictionaries may be hosted “inthe cloud” as part of a cloud computing implementation. In anembodiment, external dictionary servers may be used to centralize theconfiguration of the protocol capabilities. In an embodiment, thedynamic context router may access partial dictionaries to receive onlythe minimum amount of a rule or rules required to successfully decodemessages, reducing latency and improving processing speeds.

In an embodiment, the dynamic context router may decode messages inmultiple phases. For example, the dynamic context router may decode onlya small portion of a message in a first phase and, if necessary, performmore extensive decoding operations in a second phase. In an embodiment,the need for the second phase of decoding may be determined based on thefirst phase decoding results and/or any combination of contextual andstatic information.

In an embodiment, the dynamic context router may incrementally decodemessages. In this embodiment, incremental decoding may begin withdecoding an initial portion of the message, and determining if thedecoded portion identifies a destination component or if the destinationcomponent can be derived from the decoded portion. When it is determinedthat the previously decoded portions do not identify the destinationcomponent and/or that the destination component cannot be derived usingthe previously decoded portions, the dynamic context router may thenrecursively decode subsequent portions of the message. The need for thecontinued decoding of additional portions of the message may be based onwhether or not information extracted from the decoded portions may beused by the dynamic context router to identify a destination component.

In an embodiment, the dynamic context router may perform opaque proxyoperations. In this embodiment, if the dynamic context router receives amessage that is either partially syntactically or semantically invalid(and thus “opaque”), instead of sending an error message, the dynamiccontext router may decode only a portion of the message, leaving therest of the message in the original format (e.g., binary wire format),package the message into a network transparent container, and send thecontainer including the message to the destination node. In this manner,the dynamic context router may operate in a loose, tolerant mode thatimproves processing speeds, while supporting network nodes that do notfully comply with a particular standard.

In an embodiment, the dynamic context router may perform protocoltranslation operations. In an embodiment, the dynamic context router mayinclude a flexible protocol translator module which converts receivedmessages from a first protocol into a second protocol. In variousembodiments, the first protocol may be the same as the second protocol,a subset of the second protocol, a superset of the second protocol,compatible with the second protocol, or completely independent of thesecond protocol.

In an embodiment, the dynamic context router may perform protocoltranslation operations even when the first and second protocols are thesame.

Often, network nodes vary in their implementation of the same set ofstandards. This often occurs when the nodes are manufactured bydifferent vendors or are operating different versions of software. Forexample, a vendor's implementation of a standard may not fully complywith the standards, the standards may have changed since the nodes weredeployed, or there may be differences in implementations due tonon-standard extensions. In such cases, messages originating from asource node may not be accepted by a destination node, even though thesource node and the destination node implement the same protocol. Insuch cases, the dynamic context router may identify the differences inthe implementations and change the structure and/or the content of themessages to ensure that the messages will be accepted by the destinationnode. This embodiment improves network efficiency by providing aprotocol agnostic interface between source and destination nodes in anetwork. Source nodes may communicate with the dynamic context routerusing any protocol supported by the dynamic context router, and do notneed to be informed of the protocols supported by the destination nodes.New instances of any destination node may be added to the networkwithout informing the source nodes of the existence of the newdestination node or of the protocols associated with the new node.Likewise, new instances of the source nodes may be added to the networkwithout requiring the new source nodes to be informed of the other nodesin the network, their protocols, or the other intimate details of thenetwork.

In an embodiment, the dynamic context router may perform protocoltranslation operations when the first protocol is completely independentof the second protocol. For example, the dynamic context router mayreceive hypertext transfer protocol (HTTP) messages and convert themessages into Diameter messages.

The dynamic context router may provide a protocol agnostic interfacebetween source and destination nodes in a network which may serve toprovide topology hiding and allow inter-protocol communication within anetwork. In an embodiment, the dynamic context router may operate asboth a server and a client to further facilitate topology hiding. Asmentioned above, the dynamic context router may receive messages fromsource nodes in a first protocol and send messages to a destination nodein a second protocol. In an embodiment, the dynamic context router mayremove all network specific information for each of the messages that itrelays such that the source and destination nodes cannot determine thenetwork topology through which the messages where routed. In anembodiment, the dynamic context router may perform physical topologyhiding operations by removing all addressing information that mayidentify the location of the source nodes to the destination nodes, andthe destination nodes to the source nodes.

The various embodiments provide scalable, distributed, highly availabledynamic context router (DCR) systems capable of fast and efficientexpansion. As discussed above, operator networks are expanding at anunprecedented rate. As these operator networks expand, so will theamount of signaling traffic that must be processed by each dynamiccontext router. To support this anticipated increase in workload, thevarious embodiments provide highly-available, highly-scalable dynamiccontext router systems that can support the addition of resources (e.g.,additional cores, memories, servers, etc.), while maintaininghigh-availability.

The various embodiments provide dynamic context router systemsconfigured to manage component failures. The dynamic context router maymanage component failures by performing failover operations thatautomatically switch over to a redundant component (e.g., blade, server,DCR core, memory, network node, etc.) upon the failure or abnormaltermination of a component. As new resources are introduced into thenetwork and the dynamic context router systems, the probability of oneor more components (e.g., server, processor, hard drive, DCR core,memory, etc.) failing increases. Various embodiments provide dynamiccontext router systems configured to perform multi-level and multi-tierfailover operations that ensure continued dynamic context routeroperations in the event of multiple component failures. In anembodiment, the dynamic context router system may be deployed inredundant pairs configured in a distributed array architecture with workload balancing schemes which, in combination, ensure continued dynamiccontext router operations in the event of failures.

As mentioned above, for reasons of availability and scalability it iscommon for multiple instances of particular network elements to bedeployed within the same operator network. The deployment of multipleinstances of the same component within a single network gives rise toboth functionality and configuration overhead. Further, in cases wherepeer relationships traverse administrative boundaries, the networktopology may be exposed across that boundary. Telecommunication systemoperator networks are particularly exposed in this regard, especiallywith the emergence of inter-operator Diameter applications, such as S9and S6a. To meet these and other concerns, the various embodimentsprovide an extensive and flexible routing logic engine that may beconfigured to act as a network edge termination point or landing zonefor roaming partners wishing to participate in these types of (e.g.,Diameter) relationships.

In an embodiment, the dynamic context router (DCR) may performapplication-level topology hiding operations. Certain protocols (e.g.,Diameter) have application-level addresses. For example, each Diametermessage includes a Diameter address (e.g., Origin-Host address) builtinto the structure of the messages that cannot be removed. In variousembodiments, the dynamic context router may receive messages from sourcenodes, decode the message contents and store them in a memory, terminatethe message, and create a new message that includes all of the storedcontents, but not the address information of the source node.

In an embodiment, the dynamic context router may operate as a softwareappliance (i.e., may run on commodity hardware) that is capable ofrouting and load balancing network traffic using both static and contextbased routing rules.

The various embodiments may be implemented within a variety ofcommunication systems, an example of which is illustrated in FIG. 1.Wireless devices 102 may be configured to send and receive voice, dataand control signals to and from a service network 36 (and ultimately theInternet) using a variety of communication systems/technologies (e.g.,GPRS, UMTS, LTE, cdmaOne, CDMA2000™). For example, general packet radioservice (GPRS) data transmitted from a wireless device 102 is receivedby a base transceiver station (BTS) 12 and sent to a base stationcontroller (BSC) and/or packet control unit (PCU) component (BSC/PCU)18. Code division multiple access (CDMA) data transmitted from awireless device 102 is received by a base transceiver station 12 andsent to a base station controller (BSC) and/or point coordinationfunction (PCF) component (BSC/PCF) 22. Universal mobiletelecommunications system (UMTS) data transmitted from a wireless device102 is received by a NodeB 14 and sent to a radio network controller(RNC) 20. Long term evolution (LTE) data transmitted from a wirelessdevice 102 is received by an eNodeB 16 and sent directly to a servinggateway (SGW) 28 located within the EPC 40.

The BSC/PCU 18, RNC 20 and BSC/PCF 22 components process the GPRS, UMTSand CDMS data, respectively, and send the processed data to a nodewithin the EPC 40. More specifically, the BSC/PCU 18 and RNC 20 unitssend the processed data to a serving GPRS support node (SGSN) 24 and theBSC/PCF 22 sends the processed data to a packet data serving node (PDSN)and/or high rate packet data serving gateway (HSGW) component(PDSN/HSGW) 30. The PDSN/HSGW 30 may act as a connection point betweenthe radio access network and the IP based PCEF/PGW 32. The SGSN 24 isresponsible for routing the data within a particular geographicalservice area and may send signaling (control plane) information (e.g.,information pertaining to call setup, security, authentication, etc.) toa mobility management entity (MME) 26. The MME may request user andsubscription information from a home subscriber server (HSS) 42, performvarious administrative tasks (e.g., user authentication, enforcement ofroaming restrictions, etc.), select a SGW 28, and send administrativeand/or authorization information to the SGSN 24.

Upon receiving the authorization information from the MME 26 (e.g., anauthentication complete indication, an identifier of a selected SGW,etc.), the SGSN 24 sends the GPRS/UMTS data to a selected SGW 28. TheSGW 28 stores information about the data (e.g., parameters of the IPbearer service, network internal routing information, etc.) and forwardsuser data packets to a policy control enforcement function (PCEF) and/orpacket data network gateway (PGW) 32. The PCEF/PGW 32 sends signalinginformation (control plane) to a policy control rules function (PCRF)34. The PCRF 34 accesses subscriber databases, creates a set of policyrules and performs other specialized functions (e.g., interacts withonline/offline charging systems, application functions, etc.) and sendsthe intelligent policy rules to the PCEF/PGW 32 for enforcement. ThePCEF/PGW 32 implements the policy rules to control the bandwidth, thequality of service (QoS), and the characteristics of the data, andservices being communicated between the service network 36 and the endusers.

FIG. 2 illustrates various logical components in an examplecommunication system 100 suitable for implementing the variousembodiments. Wireless devices 102 may be configured to communicate via acellular telephone network, a radio access network (e.g., UTRAN, RAN,etc.), WiFi network, WiMAX network, and/or other well known technologies(e.g., GPRS, UMTS, LTE, cdmaOne, CDMA2000™). FIG. 2 illustrates thatwireless devices 102 may be configured to transmit and receive voice,data, and control signals to and from a base station (e.g., basetransceiver station, NodeB, eNodeB, etc.) 104. The base station may becoupled to a controller (e.g., cellular base station, radio networkcontroller, service gateway, etc.) operable to communicate the voice,data, and control signals between mobile devices and to other networkdestinations. In the illustrated example of FIG. 2, the base station 104communicates with an access gateway 110, which serves as the primarypoint of entry and exit of wireless device traffic and connects thewireless devices 102 to their immediate service provider and/or packetdata networks (PDNs). The access gateway 110 may include one or more ofa controller, a gateway, a serving gateway (SGW), a packet data networkgateway (PGW), an evolved packet data gateway (ePDG), a packet dataserving node (PDSN), a serving general packet radio service support node(SGSN), or any combination of the features/functions provided thereof.Since these structures are well known, certain details have been omittedin order to focus the descriptions on the most relevant features.

The access gateway 110 forwards the voice, data, and control signals toother network components as user data packets, provides connectivity toexternal packet data networks, manages and stores contexts (e.g. networkinternal routing information, etc.), and acts as an anchor betweendifferent technologies (e.g., 3GPP and non-3GPP systems). The accessgateway 110 may coordinate the transmission and reception of data to andfrom the Internet 107, as well as the transmission and reception ofvoice, data and control information to and from an external servicenetwork 120 connected to the Internet 107, to other base stations 104and to wireless devices 102. The access gateway 110 may also routecontrol information to a policy and charging control (PCC) network 112,which may be a part of an implementation of an evolved packet core(EPC)/long term evolution (LTE) architecture. In the variousembodiments, the access gateway 110 may be a part of the policy andcharging control network 112, and the functions described may beimplemented in a single computing device or in many computing devicescoupled in a local area network or wide area network using any of theabove mentioned telecommunication technologies (e.g., 3G, 4G, GPRS,UMTS, LTE, etc.).

Returning to FIG. 2, as mentioned above, the access gateway 110 routescontrol/signaling information (e.g., call setup, security,authentication, charging, enforcement of policy rules, etc.) to thepolicy and charging control (PCC) network 112, which is an example of atelecommunications signaling network. The PCC network 112 providespolicy and service control rules, controls charging functionalities, andprovides quality of service (QoS) authorizations, as discussed infurther detail below. The PCC network 112 may include one or morecomponents for a policy and charging enforcement function (PCEF) 114, apolicy charging rules function (PCRF) 116, an off-line charging system(OFCS) 118, an on-line charging system (OCS) 120, a subscriber profilerepository (SPR) 122, and an application function (AF) 124. Componentsin the PCC network 112 (e.g., PCEF, PCRF, OFCS, OCS, SPR, AF) maycommunicate using a standardized protocol, such as the Diameterprotocol, remote authentication dial in user service (RADIUS) protocol,session initiation protocol (SIP), or any other protocol.

To focus the discussion on the relevant features and functionalities,the various embodiments are described with reference to the Diameterprotocol. However, it is to be understood that the various embodimentsare protocol agnostic and should not be limited to the Diameter protocolunless expressly recited in the claims.

FIG. 3 is an architectural diagram illustrating communications betweenthe various logical components in a PCC network 112. The PCC network 112may include a policy and charging enforcement function (PCEF) component114 that serves as the primary enforcement point, gateway and a routingmechanism between the Internet and the radio infrastructure/radio accessnetwork. As discussed above, the PCEF component 114 may be a part of, orperform operations typically associated with, a gateway GPRS supportnode (GGSN), a packet data network gateway (PGW), or other similarcomponents. Detailed information about policy and charging enforcementfunction operations may be found in “3rd Generation Partnership ProjectTechnical Specification Group Services and System Aspects, Policy andCharging Control Architecture,” TS 23.203 (updated Jun. 12, 2011), theentire contents of which are incorporated herein by reference.

The PCEF 114 may receive signaling messages from a gateway (e.g., AccessGateway 110 illustrated in FIG. 2) and use information contained withinthe signaling messages to select an optimal route and a quality ofservice (QoS) for a particular type of services, as well as to enforcevarious policies on those services. The enforcement of policies mayinclude querying, coordinating, removing, revoking and/or adjustingvarious resources (e.g., network resources, subscriber resources, etc.)based on a set of policy rules.

The PCEF 114 enforces policies by implementing a set of policy rules.Each policy rule may govern the services, QoS, and/or bandwidth that areto be made available to a particular subscriber. The policy rules mayalso govern the times when certain services are made accessible to thesubscriber (e.g. weekdays from 9 AM to 5 PM, etc.) and how long thesubscriber may access those services (e.g., 15 minutes at a time, atotal of two hours, etc.)

The PCRF 116 is responsible for identifying the appropriate policy rulesfor a given communication session of a given subscriber or terminaldevice, and sending the identified policy rules to the PCEF 114 forenforcement. Specifically, the PCRF 116 is responsible for generating,compiling, and selecting a set of business and technology rules thatdefine the policies that are to be enforced for particular callsessions. The PCRF 116 may make rule decisions on a per-subscriber,per-session and/or per-service basis. For example, the PCRF 116 may usesubscriber information (e.g., subscriber's city of residence), thecurrent usage parameters (e.g., day of week, time of day, peak hours,etc.), the subscriber's service level (e.g., Gold, Bronze, etc.), andother information related to the subscriber, session, or service togenerate and/or select one or more rules or a rule group. The selectedrules or rule group may be communicated to the PCEF 116 (e.g., via theGx interface) as a profile that defines the policies to be enforced. ThePCRF 116 may include one or more databases for storing default rules,maintaining generated rules and keeping track of session information.

The PCRF 116 may request subscriber profile information from thesubscriber profile repository (SPR) 122, which maintains subscriberprofiles (e.g., customer IDs, preferences, subscription levels,balances, etc.) in one or more data stores.

An application function (AF) 124 represents a node involved in thedelivery of an application or service (e.g., voice-over-IP, voice andvideo call, video-on-demand, etc.) that may be used by a subscriber orthat may have dealings with the subscriber. The AF 124 may communicatewith the PCRF 116 to ensure that the generated rules are sufficient toprovide subscribers with a quality of service (QoS) commensurate withthe requirements of their requested services/flows. For example, if acurrent policy is being enforced based on rules for receiving aparticular service (e.g., a voice-over-IP call) and the subscriberrequests an additional amount of a given service, or another service(e.g., a voice and video call), the application function 124 componentmay push a new set of rules to the PCRF 116 reflecting the servicechanges (e.g., QoS, etc.) required for the additional services. Theapplication function may also store information unique to eachsubscriber, service, session, and/or application.

In addition to receiving rules from the PCRF 116, the PCEF 114 componentmay also communicate with an on-line charging system (OCS) 120 and anoffline charging system (OFCS) 118 to identify the policies that are tobe enforced and/or to ensure proper charging. For example, the PCEF 114may periodically inform the OFCS 118 of the amount of wireless data thatis being used by a subscriber. The OFCS 118 may use this information tomonitor the aggregate amount of data/service used by each subscriber,and to generate a record that may be collected, processed, formatted,correlated, aggregated, filtered, and/or sent to an external billingsystem for processing into a billing statement. In order to monitor thedata/service usage of each subscriber, the OFCS 118 may storeinformation related to each subscriber, session, and/or service.

The PCEF 114 may also periodically inform the OCS 120 of servicesrequested by a subscriber. The OCS 120 is generally responsible fordetermining if the subscriber has sufficient funds/credits/access unitsto receive a requested service. In various embodiments, the OCS 120 mayalso perform other operations related to charging, balance managementand real time rating. The OCS 120 may grant or deny access based on theamount of fund/credits/access units available. In an embodiment, the OCS120 may manage pre-pay services. In an embodiment, the OCS 120 maymanage a combination of pre-pay and post-pay services in which some (ora portion) of the services require a pre-paid balance and some (or aportion) of the services may be billed to the client. In any case, thePCEF 114 may issue requests for service authorization to the OCS 120,and the OCS 120 may respond with a message granting or denyingauthorization. As part of its operations, the OCS 120 may storeinformation unique to each subscriber, session, and/or service.

FIG. 4 is an architectural diagram illustrating the use of Diameterapplications for communications between the various logical componentsin an example policy and charging control (PCC) network 400. Asmentioned above, the logical components may communicate using aprotocol, such as RADIUS, SIP or Diameter. Diameter is a protocolstandardized by the Internet Engineering Task Force (IETF) and adoptedby the Third Generation Partnership Project (3GPP). Diameter is anextensible protocol that provides a general mechanism for two or morenodes in a network to communicate signaling information (e.g.,communications involving call setup, security, authentication, charging,enforcement of policy rules). Diameter also includes numerous accesscontrol features that make it highly useful in authentication,authorization, and accounting (AAA) systems as well as in the policy andcharging control network 112. Detailed information about the Diameterprotocol may be found in “Network Working Group Request for Comments:3588; Diameter Base Protocol,” the entire contents of which are herebyincorporated by reference for purposes of disclosing the protocoldetails.

The Diameter protocol provides a base protocol (i.e., “Diameter baseprotocol”) and a framework for defining custom extensions (i.e.,“Diameter applications”) to the base protocol. The base protocol definesa set of generic messages useful for low-level operations (e.g.,establishing connectivity, hand-shaking, etc.) and the framework allowsapplication-developers to develop Diameter applications (i.e.,extensions of the Diameter base protocol) that define custom messagesfor more specialized operations. By extending the Diameter baseprotocol, Diameter applications may use all of the features provided bythe Diameter base protocol, as well as any custom protocol extensionsthey define. For example, a Diameter application may use Diameter baseprotocol components to define exactly how messages are to becommunicated and define custom extensions that describe the content ofthe messages being communicated.

As mentioned above, logical components (e.g., PCEF 114, PCRF 116, AF124, SPR 122, OCS 120, OFCS 118) in the PCC network 400 may use theDiameter protocol to communicate with each other. Components that usethe Diameter protocol may support various standardized Diameterapplications (e.g., Gx, Gy, Gz, Rx, Sy, etc.) that are especially wellsuited for their specialized operations.

The logical components (e.g., PCEF 114, PCRF 116, AF 124, SPR 122, OCS120, OFCS 118) in the PCC network 400 may also communicate withresources outside of the provider network. For example, the PCRF 116 ina home provider network may need to communicate with a PCRF 410 inanother provider network, such as while a subscriber's cell phone roamsin the other provider's network. The external PCRF 410 may communicatewith the appropriate logical components (e.g., PCRF 116, OCS 1201, etc.)in the home provider network to ensure proper charging, QoS, charging,etc. In the illustrated example, the external PCRF 410 communicates withPCRF 116 through the S9 interface.

To focus the discussion on the relevant features, various logicalcomponents (e.g., PCEF, PCRF, AF, SPR, OFCS, OCS, etc.) are described asusing specific Diameter protocols. However, it should be understood thatany protocol may be used (e.g., RADIUS, SIP, etc.) and nothing in theclaims should be limited to a particular interface, protocol orapplication, unless expressly recited in the claims.

FIG. 5 illustrates the message structure of an example Diameter message502 suitable for encoding signaling information. Diameter messages 502have a fixed structure that includes a message header portion 504 and amessage payload/body portion 506. The message header 504 containsgeneral information about the message, such as version information 512,bit flags 514, message length 516, a command code 518, an application ID520, a hop-by-hop identifier 522, and an end-to-end identifier 524. Theversion information 512 field identifies a Diameter protocol version.The bit flags 514 provide administrative information that may be used toprocess the message. For example, the first bit (“R”) may indicate ifthe message is a request or an answer, the second bit (“P”) may indicateif the messages must be processed locally or is proxiable (e.g., may beproxied, relayed, or redirected), the third bit (“E”) may indicate ifthe message is a standard message or an error message, the fourth bit(“T”) may indicate if the messaging is being sent for the first time orif there is a probability that the message is being re-transmitted, etc.The application ID 520 identifies a type of application (authentication,accounting, vendor specific, etc.) to which the message is related. Thehop-by-hop identifier 522 is a unique ID that may be used to matchrequests to answers and send answer messages back to the requestingcomponent. The end-to-end identifier 524 is a time-limited ID generatedby the originator of a request message that should not be changed byintermediate network nodes or by the responder to the message. It isused for correlating responses with requests and for detecting duplicatemessages.

The command code 518 identifies a message type of the Diameter message502. There are several standard Diameter message types (e.g.,Accounting-Request, Device-Watchdog-Answer, etc.) defined by theDiameter base protocol. Network components may quickly identify the typeof information carried by a particular Diameter message 502 by examiningthe command code message header 504. For example, a node receiving an“Accounting-Request” message needs only examine the command code (e.g.,“271”) in the message header 504 to identify the message as anaccounting message.

The Diameter message body 506 contains the actual data/signalinginformation that is being communicated. The signaling information may bestored in one or more attribute-value-pairs (AVPs) 508, which may nestother attribute value pairs (nested AVPs) 510. Attribute-value-pairs508, 510 are extendable data-structures that include a header portion526 and a data portion 528. The header portion 526 may include generalinformation about the attribute-value-pair, such as an AVP code 530,message length 532, an optional vendor ID 534, and various bit flags536. The data portion 528 may store simple data (e.g., integer,unsigned, float, etc.) or complex data (e.g., other AVPs), in an encodedformat. The data portion 528 may encapsulate protocol-specific data(e.g., routing information) as well as authentication, authorization, oraccounting information.

The AVP code 530 field may identify an AVP type. The Diameter baseprotocol defines a number of standard AVP types (i.e., attributes).Diameter applications extending the base protocol inherit all of the AVPtypes defined by the base protocol and may define new AVP types uniqueto each application. AVP codes may be combined with the optionalvendor-ID 534 field to uniquely identify an attribute.

FIG. 6 illustrates an expanded policy and charging control (PCC) network600 having more than one instances of each of the PCEF (114 a-c), PCRF(116 a-c), AF (124 ac), OCS (120 a-c) and/or OFCS (118 a-c) components,as well as a connection to an external PCRF 410. As operator networksexpand to meet increased traffic and user demands, multiple instances ofthe same component may be implemented within a single policy andcharging control network 600. Each instance may be uniquely addressableand store information relevant to a particular service, application,session or subscriber in a local memory or database. For example, thefirst time a destination component (e.g., PCRF 116 a) receives aDiameter message from a source component (e.g., PCEF 114 a) for aparticular subscriber, the destination component (PCRF 116 a) may storesession information related to that subscriber in a local sessiondatabase. Subsequent Diameter messages may require access to the sessioninformation stored by that particular instance of the destinationcomponent (e.g., PCRF 116 a). Before the introduction of the DRA therewas no method for identifying the desired instances of components withinthe policy and charging control network 600, and each component wasrequired to discover the correct instance by trial and error. As theoperator networks continue to grow, managing communications between thevarious instances of the various components in a PCC network in a secureand efficient manner is becoming ever more important.

FIG. 7A illustrates the role of a Diameter routing agent (DRA) 702 in anexpanded policy and charging control (PCC) network 700. A Diameterrouting agent is a concept introduced by 3GPP in its specifications forfacilitating Gx, Gxx, S9, and Rx communications with a particularinstance of a PCRF (e.g., 116) when multiple and separately addressablePCRFs (e.g., 116 a-c) are deployed in the same Diameter realm. Sourcecomponents can send messages to a Diameter routing agent (as opposed tothe destination node) and rely on the Diameter routing agent to forwardthe message to the appropriate node. This allows the routing logicrequired to identify and locate a destination node to be decoupled fromthe source nodes and included in a specialized component (i.e., theDiameter routing agent).

However, the 3GPP specifications only identify the general role of aDiameter routing agent (DRA) in a Diameter network, which is to providea proxy, relay or redirect services in networks having multiple PCRFs.For example, in a PCC network 700, the role of a Diameter routing agent(e.g., DRA 702) may be to manage PCEF 114 a communications (e.g., Gx-1,Gx-2) with various instances of the PCRF (116 a, 116 b) by receiving Gxmessages and relaying the Gx messages to the correct instance of thePCRF 116. The Diameter routing agent (e.g., DRA 702) may also managecommunications (e.g., Rx-1, Rx-2) between the various instances of thePCRF 116 and AF 124 by performing simple proxy, relay or redirectoperations.

While the Diameter routing agents (e.g., DRA 702) may simplify routingoperations in a policy and charging control (PCC) network, they areprimarily focused on routing messages involving policy control rulesfunctions (PCRFs). In particular, Diameter routing agents only supportspecific interfaces (e.g., Gx, Gxx, S9 and Rx); do not performintelligent routing operations, are unaware of the context of themessages; cannot augment messages; do not support dynamic operations; donot have built-in support for future protocols/Diameter applications;cannot hide the network topology; cannot perform true translationoperations; cannot covert messages into different protocols, and are notresilient in the event of failover.

FIG. 7B illustrates an expanded policy and charging control (PCC)network 700 that includes a dynamic context router (DCR) 706 inaccordance with the various embodiments. A dynamic context router 706 isflexible, protocol agnostic, application-level router and load balancerthat may be used to manage communications between the various instancesof the various components in a network to ensure that the correctmessages are sent to the correct instances. Some of the applicationlayer functions performed by the dynamic context router 706 may includeidentifying communication partners, and determining resourceavailability. The identification of communication partners may includedetermining the identity and availability of communication partners foran application requesting a communication session to transmit data.

The dynamic context router 706 allows the routing logic required toidentify and locate a destination node to be decoupled from the sourcenodes. Source nodes may communicate with the dynamic context router 706using any Diameter application (e.g., Gx, Gy, Gz, Rx, Sy, etc.) and donot need to know the protocol requirements and Diameter applications ofthe destination nodes. In this manner, new instances of any destinationnode may be added without having to inform the source nodes of theexistence of the new destination node or of the protocols associatedwith the new node. Likewise, new instances of the source nodes may beadded to the PCC network 700 without informing the new nodes of theother nodes (and vice versa), their protocols, or other intimate detailsof the PCC network 700.

The dynamic context router 706 may make routing and load-balancingdecisions dynamically for each instance of an application/message basedon the context and content of the data being communicated. The dynamiccontext router 706 may look inside the messages being communicated andmake intelligent decisions based on the content of the messages. Thedynamic context router 706 may make calls (e.g., function calls, etc.)to external systems to request additional information for a specificmessage being communicated. The dynamic context router 706 may receiveadditional information from external systems and use the information toaugment the message, to aid in message routing, and/or to accomplishload balancing operations. The dynamic context router 706 may storeinformation specific to a particular network node, protocol,application, message or message type in an internal memory, andreference the internal memories for message processing. Asinternal/external data changes, the dynamic context router 706 mayupdate the routing and load balancing decision-making logic to reflectthe changes in internal/external data.

In an embodiment, the dynamic context router may enable node upgradeswithout interrupting service. For example, a first PCEF in communicationwith a single PCRF (e.g., using Gx) may require upgrades or may need tobe replaced without interrupting the service. The dynamic context routerallows a second PCRF to be introduced into the network without anyinterruption of service by routing old messages (e.g., all existing Gxsession messages) to the first PCRF, and all new message (e.g., new Gxsession messages) to the second PCRF. The dynamic context router mayindicate when all of the old sessions have terminated, indentifying whenthe old PCRF can be safely removed. In an embodiment, a dynamic contextrouter may be removed from the network after the new PCRF is introducedwithout interrupting operations. In an embodiment, a dynamic contextrouter may be introduced into the network along with, or immediatelyprior to, the second PCRF and removed from the network after the newPCRF is introduced.

In an embodiment, the dynamic context router may use contextualinformation obtained from response messages to influence future routingdecisions. This contextual information may be either intentionallyplaced within the response message for use by the dynamic contextrouter, or it may normally be there. For example, a dynamic contextrouter that is load balancing between five equal PCRFs may initially usea round-robin algorithm. However, some requests may require moreprocessing than others, and the PCRF loads may differ. In an embodiment,each PCRF may include an additional proprietary parameter in theresponse messages indicating its current work load, which may be used ascontextual information by the dynamic context router when making futureload balancing routing decisions.

In an embodiment, the dynamic context router may utilize a PCRF that ishighly optimized for a very limited set of functionality (e.g., a “Voiceover LTE” optimized PCRF). For example, when the dynamic context routeris routing a message to a PCRF it may use contextual information tochoose the right type of DCR. As another example, the dynamic contextrouter may be configured to host simple application logic such that if acertain type of service is not permitted in the network (regardless ofall other criteria such as user details) the DCR can respond to therequest message directly without needing to send the request message toa PCRF. Thus, in an embodiment, the dynamic context router may shieldthe PCRFs from additional and unnecessary communications and work.

FIG. 8 illustrates logical components and communication links of anexample dynamic context router system 800. The dynamic context routersystem 800 may include a dynamic context router core (DCR core) 814module, a plurality of internal resources 816, and communication links832, 834. The communication links 832, 834 may link the dynamic contextrouter system 800 to various external resources, such a dictionaryserver 840, an Oracle™ server 808, a lightweight directory accessprotocol (LDAP) server 810, as well as other external resources 812(e.g., a subscriber profile repository, an online charging system,etc.). The internal resources 816 may include in-memory databasetechnologies such as a reference database 802, as well as a plurality ofsession stores 804 and a cache memory 806. The internal resources 816may be on the same chip, on the same computing device, within the samerealm, or in the same network as the DCR core 814. The session storesdatabase 804 may include a DCR-specific session store, a general sessionstore and a session store for each message/session/node/Diameterapplication serviced by the dynamic context router.

The reference database 802 may store any type of information that willaid DCR core 814 operations, such as message formats, message processingrules, validation rules, node IDs, etc. The reference database 802 maybe populated by data from external sources 830. In such cases the datamay either be pulled by the reference database 802 from the externalsources 830, or pushed to the reference database 802 by the externalsources 830. As discussed below, the session stores 804 may storesession information, which may be used to establish “session stickiness”and/or maintain session states. The cache memory 806 may be populated bythe DCR core 814, which may periodically cache data in response toon-going dynamic context router operations. For example, the DCR core814 may cache information received from external sources useful forprocessing future messages. In an embodiment, the DCR core 814 mayperform cache-optimizing operations to identify the most expensiveinformation requests (e.g., requests made to external systems havingslow response times) and store information associated with the mostexpensive information requests in the cache memory 806. In anembodiment, the DCR core 814 may first seek information from the cachememory 806 before attempting to access external resources. In anembodiment, the dynamic context router may periodically expire or removeinformation from the cache memory 806. In an embodiment, the dynamiccontext router may perform cache-optimization operations to determine anoptimal cache-expiration rate and expire/remove information at theoptimal rate.

The dynamic context router (DCR) may use the communication links 834 toaccess one or more dictionary servers 840, which may include one or moredictionaries. Each dictionary may define information specific to aparticular protocol, application, node or message type. For example, adictionary may include file definitions, a list of available commands(e.g., “deduct balance,” “refund balance,” etc.), a list of mandatorymessage types, a list of optional message types, a list of unsupportedmessage types, field/message descriptions, and message decoding rules.The list of available commands may include a list of specific messagetypes, each of which may be associated with a specific validation rule.A dictionary may also define message requirements, such as rules forstoring certain message fields (e.g., session ID must be at the end ofthe message, session ID cannot be in the middle of the message, etc.)for a given node, protocol, or application.

The dictionary servers 840 enable the dynamic context router to supportany current or future Diameter applications and/or message formatsthrough dictionary updates. For example, if a vendor develops a newDiameter application “Z”, the vendor may add a new Diameter dictionary(dictionary entries) that defines the rules/requirements of the newapplication. In an embodiment, the DCR core 814 may dynamically generateand/or update the dictionary definitions, without requiring any of thedictionaries to be taken offline.

FIG. 9 illustrates example signaling flows in a network 900 in which adynamic context router 920 has been deployed. The network 900 mayinclude a plurality of nodes (902 a-c, 904 a-b, 906 a-d) that providespecific functions and/or implement specific protocols (A, C, E).Multiple nodes in the network 900 may provide the same function and/orimplement the same protocol. Nodes that provide the samefunctions/implement the same protocol may be different instances of thesame node (e.g., Node A, Node C, Node E). In an embodiment, the network900 may be a policy and charging control network, each of A, C and E maybe any of the logical components described above (e.g., PCEF, PCRF,OFCS, OCS, SPR, and/or AF) and each of nodes 902 a-c, 904 a-b and 906 admay be an instance of one of the logical components.

Returning to FIG. 9, a source node (e.g., 902 a-c, 904 a-b) may send arequest message (e.g., a connection request) to the dynamic contextrouter 920, which receives the request message and establishes aconnection (e.g., 910 a-c, 912 a-b) with the requesting source node. Inan embodiment, the connection may be a physical link layer communicationline. Source nodes (902 a-c, 904 a-b) may send signaling messages thatencode signaling data to the dynamic context router 920 over theestablished connections 910 a-c, 912 a-b. The signaling messages mayencode the signaling data in one or more Diameter messages. EachDiameter message may include a base Diameter message portion and anapplication specific Diameter message portion. The dynamic contextrouter 920 may receive the signaling messages and examine the baseDiameter message portion of the message to determine if the message mayprocessed by performing realm-based routing table look-up operations. Ifso, the dynamic context router DCR 920 may perform proxy, relay, orredirect operations, which may include performing load balancingoperations.

If the message cannot be processed by performing message-based routing(e.g., realm-based routing) table look-up operations, the dynamiccontext router 920 may perform application-level routing and loadbalancing operations to identify a suitable destination node (e.g., 906a-d) to which a corresponding signaling message is to be sent. Thedynamic context router 920 may determine if a message may be sent to anydestination node offering a particular service (e.g., any “E” node) orif the message requires a particular instance (e.g., 906 c) of thedestination node. If the message may be sent to any destination nodeoffering the service (906 a-d), the dynamic context router 920 mayperform load-balancing operations to identify a suitable instance (e.g.,906 c), establish a connection/association (e.g., connection 916 c) tothe identified instance (e.g., 906 c), encode the signaling informationinto a message, and transmit the signaling message to the identifiedinstance.

If the dynamic context router 920 determines that the messages should besent to a particular instance of the destination node (e.g., 906 a), thedynamic context router 920 may decode the message, examine the contentsof the message, perform application-level routing operations to identifythe correct instance (e.g., 906 a), establish a connection/association(e.g., connection 916 a) to the identified instance (e.g., 906 a),re-encode the decoded contents into a new message, encode the signalinginformation into a message, and transmit the signaling message to theidentified instance (e.g., 906 a).

FIG. 10A illustrates an example dynamic context router method (DCRmethod) 1000 for receiving signaling messages from a source node andsending corresponding signaling messages to a destination node. Asmentioned above, the dynamic context router may receive aconnection/association request from a source node and establish aconnection with the requesting source node. In step 1006, the dynamiccontext router may receive one or more Diameter messages over suchconnection. In step 1008, dynamic context router may decode a baseportion of the Diameter message. In determination step 1010, dynamiccontext router may perform message-based (e.g., realm-based) routingtable look-up operations to determine if an entry corresponding theDiameter message exists in the routing table (i.e., the Diameter messagematches a routing table entry). If the dynamic context router determinesthe Diameter message matches a routing table entry (i.e., determinationstep 1010=“Yes”), in determination step 1012, the dynamic context routermay determine if a “realm routing action” is a proxy operation. If it isdetermined that the realm routing action is a proxy operation (i.e.,determination step 1012=“Yes”), in step 1016, the dynamic context routermay perform operations to fully decode the message, and in step 1018,begin routing operations. If the realm routing action is not a proxyoperation (i.e., determination step 1012=“No”), in step 1018, thedynamic context router may begin routing operations.

If in determination step 1010 the dynamic context router determines theDiameter message does not match a routing table entry (i.e.,determination step 1010=“No”), in determination step 1014, the dynamiccontext router may determine if a Diameter application associated withthe Diameter message is supported. If the Diameter applicationassociated with the Diameter message is supported (i.e., determinationstep 1014=“Yes”), in step 1016, the dynamic context router may performoperations to fully decode the message. If the Diameter application isnot supported (i.e., determination step 1014=“No”), in step 1018, thedynamic context router may begin routing operations.

In determination step 1020, the dynamic context router determines if thedestination-host is specified in the Diameter message. If thedestination-host is specified in the Diameter message (i.e.,determination step 1020=“Yes”), in step 1026, the dynamic context routerperforms operations to modify the contents of the message (e.g.,augments the message) and sends the modified message to the destinationnode. If the destination-host is not specified in the Diameter message(i.e., determination step 1020=“No”), in step 1022 the dynamic contextrouter performs context routing operations to select a destinationdomain. In step 1024, the dynamic context router performs load balancingoperations to choose a specific instance of the selected destinationdomain. In an embodiment, the dynamic context router may match messageparameters against internal or external reference data to identify asuitable instance of the destination node. In various embodiments, thedynamic context router may identify and select the first availableinstance of the destination node, the most available instance of thedestination node, or the most under-utilized instance of the destinationnode, all of which may be performed with the assistance of dynamicinformation obtained in real-time from external systems (e.g., externalresources 812 illustrated in FIG. 8). In an embodiment, the dynamiccontext router may identify and select an instance of the destinationnode, such that the processing workload is distributed across the nodes,the communication traffic is minimized, the network resources areoptimally utilized, network throughput is maximized, and/or responsetime is minimized.

As mentioned above, in step 1026, the dynamic context router performsmessage modification operations (e.g., augments the message) and sendsthe modified message to the selected instance of the destination node.

FIG. 10B illustrates an example dynamic context router method 1050 fordetermining if a specific instance of a destination node is required. Instep 1052, the dynamic context router may determine if sessionstickiness has been configured for a particular Diameter message. Thedynamic context router may determine if a session exists by, forexample, comparing message information to a session identifier stored ina session store. If session stickiness has not been configured (i.e.,determination step 1052=“No”), in step 1054, the dynamic context routermay perform routing and load balancing operations to choose adestination node.

By establishing session stickiness the DCR may select the instance ofthe destination node to which a previous message related to that sessionwas sent and send all future signaling messages associated with thatsession to the same instance of the destination node. In this manner,signaling messages belonging to the same session, but originating indifferent source nodes (e.g., Nodes A and C illustrated in FIG. 9), maybe directed to the same instance of the destination node (e.g., 906 a-dillustrated in FIG. 9). If the dynamic context router determines thatsession stickiness has been configured (i.e., determination step1052=“Yes”), in step 1056, the dynamic context router may perform asession look up. In determination step 1058, the dynamic context routermay determine if the session exists by, for example, comparing sessioninformation extracted from the Diameter message to session identifierinformation stored in a session store. If the session is found (i.e.,determination step 1058=“Yes”), the dynamic context router may, in step1064, route the message to a specific destination associated with theidentified session. If the session is not found (i.e., determinationstep 1058=“No”), in step 1060, the dynamic context router may performrouting and load balancing operation to choose a destination node. Instep 1062, the dynamic context router may update the session store withthe chosen destination node.

As mentioned above, in the various embodiments, as part of theapplication-level routing operations, the dynamic context router maydetermine that a specific instance of a destination node is required.For example, the dynamic context router may determine that a Diametermessage must always be sent to a specific node due to a context basedrouting operation requiring all mobile subscriber integrated servicesdigital network numbers (MSISDNs) matching a certain pattern go to aspecific node, or due to a context based routing operation requiringthat all messages in the session go to the same destination node.

FIG. 11 illustrates logical components and information flows 1100 of anexample dynamic context router system (DCR system) 1150 configured toreceive messages from multiple instances (e.g., 902 a-904 b) of multiplesource nodes (e.g., Nodes A, C) and send corresponding signalingmessages to destination nodes (e.g., Node E, 906 a-d). The DCR system1150 may include a dynamic context router core (DCR Core) 1114 module, aplurality of internal resources 1116 and communication links to variousexternal resources, such as a dictionary server 1140 a, an Oracledatabase 1108, a Lightweight Directory Access Protocol (LDAP) database1110, etc. The internal resources 1116 may include a reference database1102, session stores 1104 and a cache memory 1106.

FIG. 11 illustrates that the DCR core 1114 may receive signalingmessages from one or more source nodes (902 a-904 b). Each signalingmessage may encapsulate signaling information (e.g., charging rules,authentication information, enforcement of policy rules, etc.).Signaling messages, such as Diameter messages, may be sent to the DCRcore 1114 using interface 1120. Each Diameter message may have encodedbase protocol portions and encoded application-specific portions. Thebase protocol portions may be decoded by any Diameter application/nodeand/or relayed or proxied accordingly. The application-specific portionsmay only be decoded if all of the application-specific decoding rulesare known by the receiving node.

Thus, in an embodiment, the dynamic context router may receive aDiameter message, decode the base Diameter portions of the Diametermessage into base parameters/AVPs, decode the application-specificportions of the Diameter message into application parameters/AVPs, usethe decoded parameters/AVPs to identify a proper destination node,re-encode the base and application parameters/AVPs into a new Diametermessage, and send the Diameter message to the identified destinationnode.

As mentioned above, the network nodes generally can only decode theapplication-specific portions of Diameter messages if all of theapplication-specific decoding rules are known to the network node. FIG.11 illustrates that the dynamic context router communicates with adictionary database 1140 a, and may request these application-specificdecoding rules from the dictionary database 1140 a. For example, the DCRcore 1114 may send a request message identifying a protocol, node, ormessage to a dictionary server (not illustrated), which receives therequest, queries the dictionary database 1140 a for the correct set ofrules and sends the rules to the DCR core 1114. The DCR core 1114 maythen use these rules to decode the application-specific portions of themessages. However, access to the external resources, such as thedictionary database 1140 a, is generally an expensive and time consumingprocess. In addition, once the DCR core 1114 receives the decodingrules, it must spend considerable processing resources to perform theactual decoding operations.

To improve efficiency and reduce latency, in an embodiment, the DCR core1114 may access partial dictionaries 1140 b and/or perform the decodingoperations in two phases. Partial dictionaries 1140 b are dictionariesthat do not contain a complete set of rules for a particular protocol,message, node or application. In an embodiment, partial dictionaries1140 b may be created out of necessity when the information stored inthe complete dictionary cannot fully describe both a newer and an olderstandard, both of which may exist simultaneously in the network. In anembodiment, partial dictionaries 1140 b may contain only the minimumamount of rules required to successfully communicate with a givenprotocol. Since partial dictionaries may contain less information thancomplete dictionaries, in an embodiment, the DCR core 1114 may utilizepartial dictionaries to receive and process the messages much fasterwhen a partial dictionary is available.

In an embodiment, the DCR core 1114 may perform decoding operations intwo or more phases. This multi-phase decoding allows the dynamic contextrouter to decode a small portion of the message and, if necessary,perform addition decoding operations in small targeted increments untila suitable destination node is identified or it is determined that asuitable destination node cannot be determined from additional decodingoperations. For example, the DCR core 1114 may incrementally decodeadditional portions of the base and/or message body until: a suitabledestination node can be identified; the entire message is decoded; orthe DCR core otherwise determines that a suitable destination nodecannot be determined from further decoding of the message.

In an embodiment, the DCR core 1114 may perform protocol translationoperations. Protocol translations may be performed at several differentlevels, and multiple translations may be performed together. Forexample, FIG. 11 illustrates that the DCR core 1114 may receive aDiameter message 1134 from a particular instance of a source node (e.g.,902 a). The message 1134 may be implemented in a first protocol (e.g.,SOAP) and require transmission to a destination node (e.g., 906 a) thatrequires a second protocol (e.g., Diameter). Since the first and secondprotocols differ, the destination node will not be able to receive themessage. In an embodiment, the DCR core 1114 converts the message fromthe first protocol into the second protocol. For example, the DCR core1114 may receive the SOAP message 1134, decode the message, performoperations to identify the destination node, perform operations toidentify the protocol supported by the destination node (e.g.,Diameter), access the dictionary databases 1140 a-b for the messagerequirements of the second protocol (e.g., Diameter), re-encode thedecoded message to implement the second protocol and send the re-encodedmessage to the destination node.

In various embodiments, the first protocol may be the same as the secondprotocol, a subset of the second protocol, a superset of the secondprotocol, compatible with the second protocol, or completely independentof the second protocol.

In an embodiment, the DCR core 1114 may perform protocol translationoperations even when the first and second protocols are compatible orthe same. Often, nodes/logical components (e.g., 902 a-906 d) vary intheir implementation of the same set of standards, especially when thenodes/logical components (e.g., 902 a-906 d) are manufactured bydifferent vendors. For example, a vendor's implementation of a standardmay be less than compliant to the standards, outdated, containproprietary extensions to the standard, or the standards may havechanged since the nodes were deployed. In such cases, messagesoriginating from a source node may not be accepted by a destinationnode, even though both the source node and the destination nodeimplement the same protocol. In an embodiment, the DCR core 1114 changesthe values of the Diameter message. In doing so, the DCR core 1114 mayperform operations of: receiving and decoding a Diameter message;decoding the AVPs contained therein; examining the contents of the AVPs;identifying a destination node; identifying the values/fields that needto be added, removed, and/or changed in order for the message to beaccepted by the identified destination node; requesting information fromthe internal and/or external resources; augmenting the message byadding, removing, or changing the identified values/fields; re-encodingthe AVPs into a Diameter message that conforms to the standards; andsending the message to the destination node.

As mentioned above, the dynamic context router may perform routingoperations, e.g. proxy, relay, and redirect operations. In order toperform these routing operations, the DCR core 1114 may determine if themessage to be routed contains information identifying a specificdestination host. If the message identifies a specific destination host,then the DCR core 1114 may forward the message to the specifieddestination host (e.g., 906 a). If the message does not identify aspecific destination host, then the DCR core 1114 may analyze themessage to determine if the message contains information identifying aspecific destination realm to which the message is to be sent. If themessage identifies a specific destination realm, the DCR core 1114 mayperform one or more routing/load balancing operations to identify asuitable destination host, supplement the message with additionalinformation (e.g., augment the message), and send the message to theidentified destination host.

As part of the context routing operations, the DCR core 1114 maycommunicate with external resources (e.g. 1108, 1110, etc.) to receivethe additional information that may be used to augment the messagesand/or aid the context routing decisions. For example, the DCR core 1114may generate one or more keys based on values/fields of the decodedmessages and send the generated keys to the external resources (e.g.,1108, 1110, etc.). The external resources (e.g., 1108, 1110, etc.) mayuse the keys to locate (e.g., lookup, pull, etc.) supplementaryinformation that may be used to aid the routing/load balancingoperations and send the supplementary data to the DCR core 1114. The DCRcore 1114 may receive the supplementary information, identify the properdestination host, add the information to the message, and send theaugmented message to the proper destination host.

As mentioned above, the DCR may send and receive messages to and fromany Diameter application, as well as other similar protocols (e.g.,SOAP, RADIUS, HTTP, etc.). Also as mentioned above, the DCR may send andreceive messages from network nodes (e.g., a subscriber profilerepository, an online charging system, etc.) and may route messages toand from such nodes. In an embodiment, the DCR core 1114 communicateswith a subscriber profile repository (e.g., SPR 122 discussed above withreference to FIG. 7B) and uses the information contained therein (e.g.,subscriber information) to augment the messages and/or identify adestination node. In an embodiment, the DCR core 1114 communicates withan online charging system (e.g., OCS 120 a-c discussed above withreference to FIG. 7B) and uses the information contained therein (e.g.,charging information) to augment the messages and/or identify adestination node. In an embodiment, the DCR core 1114 accesses anoff-line charging system (e.g., OFCS 118 a-c discussed above withreference to FIG. 7B) and uses subscriber billing/charging informationto augment the messages and/or identify a destination node.

As previously discussed, nodes/logical components (e.g., 902 a-906 d)may vary in their implementation of the same set of standards,especially when they are manufactured by a number of different vendors.In some cases, different instances of the same component may vary intheir implementation of the same standard even when manufactured by thesame vendor. For example, vendors typically upgrade their componentspiecemeal, as opposed to all-at-once, and it may take the vendors anumber of years to fully upgrade all of their components. During thistime, the upgraded components may use a newer, updated, or modifiedversion of the standards (e.g., updated message structure, rules, etc.)compared to the yet-to-be upgraded components (i.e., the unimprovedcomponents). Since the newer/upgraded components use a different versionof the standards than the older/unimproved components, during theupgrade period, the vendor may reduce complete dictionaries to partialdictionaries. In such cases, the partial dictionary is created out ofnecessity because the information stored in the complete dictionarycannot fully describe both the newer standards and the older standards,both of which exist simultaneously in the network. The variousembodiments may address such situations by performing protocoltranslation operations to cause the different versions to interoperate,by utilizing peer specific dictionaries, by performing partial decodingoperations and/or by performing tolerant decoding operations. Thepartial decoding operations may include using a partial dictionaryand/or only decoding parts of the message, as discussed in more detailabove.

In an embodiment, the dynamic context router may operate in an opaqueproxy mode that supports piecemeal upgrades. The opaque proxy mode maybe logically situated between the relay and proxy modes. The dynamiccontext router may operate in an opaque proxy mode when the dictionaryinformation is insufficient and/or when the dynamic context routersystem seeks to improve performance (e.g., intentional partialdictionary).

The dynamic context router may perform tolerant decoding operations,which may be performed as part of the opaque proxy operations. Thetolerant decoding operations may include decoding the complete messagewhile allowing errors to exist (e.g., tolerating errors). For example,the rules specified in the complete dictionary may be relaxed to allowmessages with missing mandatory AVPs (or messages with AVPs in the wrongposition) to be processed as if they do not include errors.

As discussed above, the dynamic context router may decode only a portionof the Diameter messages. When dynamic context router operates in theopaque proxy mode (i.e., as an opaque proxy agent), the dynamic contextrouter may access a partial Diameter dictionary and decode only thosefields available to it (e.g., inadvertent partial dictionary) or onlythose fields required by the destination node (e.g., intentional partialdictionary). For example, if a partial dictionary provides only five (5)out of ten (10) total definitions, instead of sending an error messageto the source node, the dynamic context router may decode the messageusing the available definitions and leave the rest of the message in theoriginal format (e.g., binary wire format). The dynamic context routermay then re-encode the decoded portions, couple them to the un-encodedportions to create an opaque message, and send the opaque message to adestination node. If, in response to sending the opaque message, thedynamic context router receives an error message from the destinationnode, the dynamic context router may re-process the message by accessinga complete dictionary and perform a full decoding operation (e.g., inthe case of intentional partial dictionary), or send an error message tothe source (e.g. in the case of an inadvertent partial dictionary).

In an embodiment, the dynamic context router system may performrouting/load balancing operations by hierarchy. For example, the dynamiccontext router system may organize the network topology into a logicalstructure that facilitates load balancing and high availability. Thelogical structure may define the nodes/resources available to thedynamic context router system and enable the dynamic context routersystem to quickly and efficiently locate nodes/resources. The logicalstructure may also identify available alternatives to each node/resourcefor fail-over operations, support the intelligent placing of new assetsin peer groups, allow for dynamic addition/removal of nodes/resources tothe dynamic context router network, and support intelligent routingbetween dynamic peers. In an embodiment, the logical structure may be atopology tree stored in memory.

FIG. 12 illustrates an example DCR topology tree 1200 that may be usedby the dynamic context router for performing routing/load balancingoperations by hierarchy. FIG. 12 also illustrates example DCR logicalcomponents 1250 for performing operations on the DCR topology tree 1200.The DCR logical components 1250 may include a business logic module1202, a peer group-level module 1204 and a peer module 1206.

It should be noted that the DCR topology tree 1200 may be implementedusing a wide variety of data structures, including arrays, trees,linked-lists, maps, vectors, and graphs. The DCR topology tree 1200 maybe configured to support root nodes, internal nodes and terminal nodes.The DCR topology tree 1200 may be configured to allow each node to havemore than one parent. The DCR topology tree 1200 may be configured toallow multiple root nodes. Thus, in various embodiments, the DCRtopology tree 1200 may be implemented using a wide variety of datastructures (e.g., arrays, trees, graphs, etc.) and is not limited to atree structure.

In an embodiment, the DCR topology tree 1200 may include domains as rootnodes, at least one peer-group as an internal node for each of the oneor more domains, and at least one peer as a terminal node for the atleast one peer-group. In an embodiment, the dynamic context router mayperform application level routing operations to identify a root node inthe topology tree and identify a terminal node destination componentusing the identified root node and hierarchical groups of the topologytree. In an embodiment, identifying a terminal node destinationcomponent using the identified root node and the hierarchical groups ofthe topology tree includes identifying and selecting the root node byperforming business rule operations, identifying and selecting internalnodes by performing at least one of partitioning operations andavailability operations and identifying and selecting the terminal nodebased on load balancing requirements.

Returning to FIG. 12, the DCR topology tree 1200 may be arranged suchthat peer nodes (e.g., peers 1-8) are grouped into peer groups (e.g.,peer groups 1-4), and peer groups are grouped into domains (e.g., domain1, domain 2) 1208, 1210. The peer nodes may be grouped such that eachpeer node belonging to a particular peer group is capable of performingthe same functions as every other peer node belonging to the same peergroup. Sine all of the nodes may be equivalent, this grouping enablesthe performance of efficient load balancing operations. Domains withinthe DCR topology tree may be defined according to business rules, e.g.domains can represent geographical areas, datacenters, subscriberranges, and/or other any other logical group. Each peer may represent adestination node 1208-1222 and/or contain a reference to a destinationnode 1208-1222. In an embodiment, each peer group may belong to morethan one domain, and each peer may belong to more than one peer group.In an embodiment, peer groups may belong to other peer groups, which mayfacilitate embodiments having multiple layers of internal nodes.

Each peer group may advertize itself as being in either an availablestate or in a not-available state. Each peer group may define the numberpeer nodes that need to be available before the peer group changes itsstate from not-available to available. Thus, Peer groups may be definedup front; pre-configured peers may be added up front; and nonpre-configured peers may be added to peer-groups at run time via regularexpression matching.

The business logic module 1202 may select a domain 1208, 1210 byperforming business-level operations by defining a set of rules, regularexpressions and/or patterns. In an embodiment, the peer group-levelmodule 1204 may select a peer group by availability (e.g., firstavailable in a chosen domain). Within the selected peer group, aspecific peer node may be chosen according to a configured loadbalancing algorithm.

In an embodiment, the topology tree may be created such that peers areexplicitly configured to belong to peer groups when the peers are added.In an embodiment, the topology tree may be created such that peers maybe assigned to peer groups based on the regular expression method. In anembodiment, the rules, regular expressions and/or patterns for theintelligent placing of new assets in peer groups may be defined in aconfiguration file accessible to the operator network.

Peer nodes may be pre-configured such that the nodes are placed into aparticular peer group as they are added to the topology tree. Forexample, a peer node may define a specific host and realm, which may beused by the dynamic context router to place the node within a particularpeer group in the topology tree. Peer nodes that connect to the dynamiccontext router system without having been pre-configured to be placedexplicitly in a specific peer group may be inserted into the topologytree by matching their host and realm information to a peer group usinga regular expression template. The dynamic context router may add eachtype of peer node (e.g., pre-configured, dynamically defined, etc.) in amanner that allows both types of peer nodes to exist within in thetopology tree.

In certain situations, a Diameter message may be routed to a peer nodethat fails before a response is received by the dynamic context router.In such situations, the dynamic context router may coordinate failoveroperations by re-traversing the topology tree to find an appropriatealternative peer to which to resend the message. For example, if aselected peer node fails, the dynamic context router may traverse up theDCR topology tree 1200 to identify the peer group to which the failingpeer node belongs, identify another available peer node within that peergroup. If no peers are available in the peer group, the dynamic contextrouter may traverse another level of the hierarchy tree to identify thefirst available peer group within the same domain, and traverse down thetree to a peer node within the identified peer group.

In an embodiment, the DCR topology tree 1200 may be generated or updatedas part of the dynamic context router performing general processing androuting operations. For example, the dynamic context router may annotatepeer destinations as they are processed to create one or more logicaloverlay networks, which may be represented by the DCR topology tree1200. The logical overlay networks may lend themselves to simplerrouting configurations by allowing routing logic to refer to an entirelogical network, instead of having to refer to each constituentdestination. For example, if it is determined that a certaingeographical area is under heavy load, the dynamic context router maychange one or more global context settings for that geographical area toallow multiple applications and routes to be updated in the DCR topologytree 1200, thereby avoiding the congested area (i.e., the geographicalarea under heavy load).

In an embodiment, the dynamic context router may prioritize the peerswithin a peer group. In an embodiment, the dynamic context router maygive each of the peers within a peer group equal priority, while inother embodiments peers may be prioritized in a flexible manner. In anembodiment, the dynamic context router may create logical sub groupingsof the peer nodes. For example, the dynamic context router may grouppeer nodes at various locations around the topology by annotating themas belonging to a group (e.g., “New York,” “Data Center X,” etc.). Inthis manner, the dynamic context router can control a large number ofindependent peers and control the execution of many different routingrules through a single command (e.g., “avoid New York”).

As discussed above, the business logic module 1202 may select a domain1208, 1210 by performing business-level operations, which may be definedby configuration. Allowing the business-level operations to be based onthe configuration provides a flexible method of grouping destinations sothat the routing operations may select a suitable destination node basedon a number of factors. For example, the DCR system may be configured todefine the domains 1208, 1210 to represent a subscriber range (e.g.,subscriber range A, subscriber range B), in which case, geography onlycomes into play at the peer group-level module 1204. In this manner, theDCR system may be configured to provide geo-redundancy, load balancingand/or failover capabilities within a single datacenter, as required.

In an embodiment, the dynamic context router may perform messagedestination address hunting operations within a network when thatinformation is not ascertainable from the message itself. As discussedabove with reference to FIG. 9, every instance of a node (e.g.,destination nodes 906 a-d) may maintain data that is unique to eachnode/subscriber/session, and some messages must be routed to a specificinstance to access this data. However, on some occasions, the correctinstance of the destination node cannot be ascertained from theinformation included within the message or otherwise available to thedynamic context router. If the decoded message does not includeinformation identifying a specific realm or destination node, andinformation retrieved from the external and internal resources (e.g.,reference databases, session stores, etc.) is not sufficient to identifya proper destination node, the dynamic context router may perform one ormore hunting operations to locate the proper instance of the destinationnode.

FIG. 13 illustrates a dynamic context router (DCR method 1300 forreceiving and sending Diameter messages in accordance with anembodiment. In step 1302, the dynamic context router may receive anddecode a Diameter message. In determination step 1304, the dynamiccontext router may determine if the decoded message identifies adestination realm. If the decoded message does not identify adestination realm (i.e., determination step 1304=“No”), in step 1340,the dynamic context router may send an error response message to thenetwork node from which the message was received. If, on the other hand,the decoded message does identify a destination realm (i.e.,determination step 1304=“Yes”), in determination step 1306, the dynamiccontext router may determine if the decoded message identifies adestination host. If the decoded message identifies a destination host(i.e., determination step 1306=“Yes”), in step 1320 the dynamic contextrouter may re-encode the message into a proper format and/or send there-encoded message to the identified destination host. If the decodedmessage does not identify a suitable destination host (i.e.,determination step 1306=“No”), in step 1308, the dynamic context routermay request/receive information from internal resources if needed. Instep 1310 the dynamic context router may request/receive informationfrom external resources if needed. In step 1312, the dynamic contextrouter may use all of the information available (e.g., information fromthe message, internal memories, external resources, etc.) to performapplication-level routing operations as discussed above.

In determination step 1314, the dynamic context router may determine ifthe above-mentioned routing operations identify a suitable destinationdomain. If the routing operations identify a suitable destination domain(i.e., determination step 1314=“Yes”), in step 1316, the dynamic contextrouter may perform load balancing operations to choose a destinationhost (e.g., a specific instance of a network node). If the routingoperation does not identify a suitable destination domain (i.e.,determination step 1314=“No”), in step 1318, the dynamic context routermay perform message destination hunting operations to identify adestination host (if configured to do so), and in step 1320, re-encodeand send the message to the destination node identified from suchhunting operations.

The node-selection operations may include selecting a node from thehierarchy tree, selecting a node based on heuristics, selecting thefirst available node, selecting a random node, performing a routingoperation, performing a randomization operation, and/or performing alearning operation. Using one of these methods, the dynamic contextrouter may select a node, encode the message into a suitableformat/protocol, send the message to the selected destination node, andwait for a response from the destination node. In determination step1322, the dynamic context router may determine whether it a negativeresponse from the selected destination node, such as the selecteddestination node rejects the message. If the dynamic context routerreceives a message acknowledgement or otherwise does not receive anegative response from the selected destination node (i.e.,determination step 1322=“No”), which indicates that the correctdestination node has been identified, the dynamic context router maystore information correlating the subscriber and/or session to thecorrect destination node in a cache memory (e.g., cache memory 1016) instep 1324 so that all future messages associated with that subscriberand/or session may be sent to that same node.

However, if the dynamic context router receives a negative response fromthe selected destination node (i.e., determination step 1322=“Yes”), thedynamic context router may add the selected node to a “do-not-use” listin memory, and update the node-selection algorithm in step 1326. In anembodiment, the “do-not-use” list may be a list of destination nodesknown not to be correlated to certain subscribers/sessions, which thedynamic context router may reference to exclude certain nodes for futureconsideration. In an embodiment, adding the selected node to a“do-not-use” list in memory may include performing operations forupdating a topology tree stored in memory to include or exclude theselected node. After receiving a negative response and updating thememory/algorithms in step 1326, the dynamic context router may un-selectthe node and repeat the above-mentioned process with the updatedmemory/algorithms by returning to determination step 1314 or step 1318.This process may continue until a correct destination node has beenidentified, as indicated by the message being accepted (i.e.,determination step 1322=“No”). Again, the dynamic context router maystore information correlating the subscriber and/or session to thecorrect destination node in a cache memory (e.g., cache memory 806) instep 1324 so that all future messages associated with that subscriberand/or session may be sent to that same node.

Message destination hunting operations may include checking (e.g., viacustomer routing logic) a user defined cache (e.g., user defined caches2024 illustrated in FIG. 20) to determine if a destination for aparticular subscriber being routed is already known. FIG. 14 illustratesin more detail a dynamic context router (DCR) method 1400 for performingmessage destination hunting operations. In step 1402, the dynamiccontext router may select a destination node. In step 1404, the dynamiccontext router may encode the Diameter message into the correctformat/protocol and send the message to the selected node. Indetermination step 1406, the dynamic context router may determine if areply has been received from the selected node. If a positive reply hasbeen received from the selected node (i.e., determination step1406=“No”), in step 1414, the dynamic context router may store (e.g., inan internal memory or resource) information correlating subscriberand/or session information to the selected destination node, andterminate further destination hunting operations for the receivedmessage. If, on the other hand, either a negative reply has beenreceived or no reply has been received from the selected node (i.e.,determination step 1406=“Yes”), in step 1408, the DCR may remove theselected node from a list of available nodes, which may be stored in aninternal memory. In step 1410, the dynamic context router may unselectthe selected node. In step 1412, the dynamic context router may updateits node selection algorithms and parameters and re-initiate thenode-selection operations (step 1402).

In an embodiment of message destination hunting operations, the dynamiccontext router may generate a list of possible destinations and routethe message to the first destination on the list in steps 1402 and 1404.In this embodiment, the dynamic context router may issue a request tothe Diameter library to store the rest of the list in an outstandingtransactions queue. In determination step 1406, the dynamic contextrouter system may examine (e.g., via custom logic in the responsehandling module/pipeline described below) response messages received inresponse to routing the message to the first destination. If a responsemessage indicates “success” (i.e., determination step=“No”), the dynamiccontext router system may terminate further hunting operations andupdate the user defined cache in step 1414. If, on the other hand, theresponses indicate that the message was not successfully transmitted toan appropriate destination node (i.e., determination step=“Yes”), thedynamic context router system may determine if there are moredestinations in the generated list, select the next destination from thelist, and send the message to the selected destination as part ofre-performing step 1402. This process of steps 1402 through 1412 may berepeated until a “successful” response message is received (i.e., anappropriate destination node is discovered) or until all of thedestinations in the list have been attempted (e.g., list is empty). Ifthere are no more destinations, then the dynamic context router systemmay deem the hunting operations as unsuccessful and send an error to theoriginating node.

In an embodiment, as part of performing the message destination huntingoperations, the dynamic context router may perform operations thatimplement a randomization algorithm. The randomization algorithm may useparameters (e.g., uniformly random parameters, concentration parameters,etc.) to guide the dynamic context router's node-selection behavior. Therandomization parameters may be selected/updated such that theaverage-case node-selection performance is greater than selecting thenodes at random.

In an embodiment, the hunting operations may include identifying andselecting nodes based on network latency, node performance, speed,capacity, workload and/or availability. In this manner, if the selectednode is not the correct destination, the dynamic context router mayquickly receive the rejection response and update thememories/algorithms accordingly.

In an embodiment, the hunting operations may continue for apredetermined amount of time or until the correct instance isidentified. In an embodiment, the message destination hunting operationsmay implement one or more learning algorithms. In an embodiment, thehunting operations may be based on heuristics.

In various embodiments, the message destination hunting operations maybe performed to locate information for a particular subscriber or asession. For example, if subscriber related information is partitionedacross multiple data nodes and messages need to be routed to aparticular node based on the location of the subscriber information,subscriber-based hunting algorithms may be applied to avoid provisioningall nodes with information about the employed partitioning scheme.Likewise, if an ephemeral session state is maintained in a particularnetwork node and other network nodes need to either query or update thatsession state, the node location may be unpredictable (e.g., due to anon-deterministic routing during session set-up). In such cases, sessionhunting algorithms may be performed to locate a node storing thepertinent session information.

In an embodiment, the caching operations may be integrated with messagedestination hunting operations.

As discussed above, telecommunications operator networks are expanding.As these networks expand and new resources are introduced, it is morelikely that a component (server, processor, hard drive, DCR core,memory, etc.) in the system will fail. The various embodiments enablemanagement of component failure by configuring dynamic context routersto perform failover operations that automatically switch over to aredundant component (e.g., blade, server, DCR core, memory, networknode, etc.) upon the failure or abnormal termination of a component. Thedynamic context router may be configured to perform multi-level andmulti-tier failover operations to ensure continued operations in theevent of multiple component failures. Moreover, the various embodimentsprovide scalable, distributed, highly available dynamic context routersystems capable of fast and efficient expansion by supporting theaddition of resources (e.g., additional cores, memories), whilemaintaining high-availability.

FIGS. 15A-17C illustrate example logical components and informationflows in embodiment DCR systems that perform failover operations andmaintain session state information in the event of a component failover.FIG. 15A illustrates example logical components in a DCR system 1500configured to maintain session state information in the event of afailover. The DCR system 1500 may include one or more pairs ofservers/DCRs, each pair including a first DCR 1502 having a first DCRcore 1504 and a first memory 1506 and a second DCR 1508 having a secondDCR core 1510 and a second memory 1512. The first and second memories1506, 1512 may be any internal resource (e.g., reference database 1102,session stores 1104, cache 1106 discussed above with reference to FIG.11) for storing information.

The DCR system 1500 may also include a communication link 1514connecting the first and second DCRs 1502, 1508. The second memory 1512may store a replica of the information stored by the first memory 1506,which may be initiated by the DCR system. In an embodiment, thecommunication link 1514 may connect the first and second memories 1506,1512 on the first and second DCRs 1502, 1508 such that any informationadded to the first memory 1506 is automatically added to the secondmemory 1512. Likewise, any information removed/expired from the firstmemory 1506 may be automatically removed/expired from the second memory1512.

Session information may be stored in the first and second memories 1506,1512 using a structure (e.g., associative array, hashtable, tree, etc.)that allows the sessions to be quickly located and retrieved from thememories. In an embodiment, the first and second memories 1506, 1512 maystore information so that the same decision logic locates the storedinformation in each physical memory. In this manner, the logic used tolocate the session states in memory is the same for both memories,despite the session state information being physically stored inseparate memories (e.g., first and second memories 1506, 1512).

FIG. 15B illustrates example information flows in an example DCR system1550 configured to maintain session state information in the event of afailover. Specifically, FIG. 15B illustrates that a source node 902 amay send a signaling message to the first DCR core 1504 over a primarycommunications link 1530 and maintain a reference to a secondarycommunication link 1532 to the second DCR core 1510. The first DCR core1504 may receive the message, identify a proper destination node (e.g.,906 a) and/or perform other DCR operations on the message. The first DCRcore 1504 may also establish session stickiness by storing sessioninformation (e.g., session 1) in the first memory 1506, which isautomatically replicated in the second memory 1512 via the communicationlink 1514.

If the first DCR core 1504 fails or does not respond to the source node902 a in a predetermined amount of time, the source node 902 a may failover to the second DCR core 1510 by sending the signaling message overthe secondary communication link 1532. Since the second memory is areplicate of the first memory 1506, the second DCR core 1510 mayretrieve the session information from the second memory 1512 and performany and all operations originally requested from the first DCR core1504, including sending the message to the destination node 906 a. Inthis manner, session state is maintained and the DCR system is resilientto the failure event.

It should be understood that the DCR systems discussed herein mayoperate in both an active-hot standby configuration, as well as in anactive-active configuration, and that each of the DCR cores maysimultaneously serve as both a primary DCR core and a secondary DCRcore.

FIG. 15C illustrates example information flows in an embodiment DCRsystem 1570 configured to provide failover support on two layers.Similar to the system described above, the source node 902 a sends asignaling message to the first DCR core 1504 over the primarycommunications link 1530 and maintains a reference to the secondarycommunication link 1532 to the second DCR core 1510. The first DCR core1504 receives the message and performs DCR operations, which may includeidentifying suitable destination nodes and storing session information(e.g., session 1) in the first memory 1506, which is automaticallyreplicated in the second memory 1512 via communication link 1514. Thefirst and second memories 1506, 1512 and the primary and secondarycommunication links 1530, 1532 provide a first layer of failoversupport.

In the illustrated example of FIG. 15C, the DCR core sends messages todestination node 906 a using DCR-1 Primary. When destination node 906 abecomes unresponsive, the DCR may select destination node 906 z (usingthe topology tree) and start sending future messages to it using DCR-1Secondary. In other words, destination node 906 z may not be chosenbefore destination node 906 a fails.

In the various embodiments, dynamic context routers may be grouped intopairs (DCR Pairs) such that each dynamic context router system includesan even number of DCR cores. This allows the session stores to bedeployed in an active-hot standby configuration while the DCR coresoperate in an active-active configuration. That is, each DCR core withinthe DCR Pair may remain active (i.e., may receive and process networktraffic) while one session store within the DCR pair remains active anda second session store within the DCR pair remains on active standby.

FIG. 16 illustrates logical components and informational flows inanother example DCR system 1600 configured to maintain session stateinformation in the event of a failover. The DCR system 1600 may includea DCR pair 1602 having a first DCR 1604 and a second DCR 1606. Similarto the DCR system 1500 described above, the first DCR 1604 may include afirst DCR core 1608 and a first memory 1610, the second DCR 1606includes a second DCR core 1612 and a second memory 1614, and acommunication link 1616 connects the first DCR 1604 to the second DCR1606, and information may be transferred such that the second memory1614 contains a replica of the session information stored by the firstmemory 1610. The DCR system 1600 also includes primary communicationslinks (DCR-1 Primary) 1618, (DCR-2 Primary) 1620 connecting the firstand second DCR cores 1608, 1612 to the first memory 1610. Likewise,secondary communications links (DCR-1 Secondary) 1622, (DCR-2 Secondary)1624 connect the first and second DCR cores 1608, 1612 to the secondmemory 1614. Each of the first and second DCR cores 1608, 1612 mayremain active (e.g., receives and processes Diameter messages), whileone of the first and second memories 1610, 1614 remains active. Thenon-active memory (e.g., 1610 or 1614) may remain in a standby mode.

A source node 902 a may send a signaling message to the first DCR core1608 over a primary communication link and maintain a secondarycommunication link to the second DCR core 1612. If the first DCR core1608 fails or does not respond to the source node in a predeterminedamount of time, the source node 902 a may fail over to the second DCRcore 1612 and send the signaling message using the secondarycommunication link. Likewise, both the first and second DCR cores 1608,1612 may read and write information to the first memory 1610 (e.g., viathe primarily communications links 1618, 1620). If the first memoryfails, both the first and second DCR cores 1608, 1612 may fail over tothe second memory 1614 to access the replicated data. In this manner,DCR system 1600 is resilient to the database/memories 1610, 1614failing, the DCR cores 1608, 1612 failing, and the DCRs 1604, 1606failing. In addition, the failure of any one component does not affectthe availability of the other components.

FIGS. 17A-17C illustrate example information flows and logicalcomponents in an example DCR system 1700 configured to provide failoversupport and maintain session state information across partitions (e.g.,partitions 1730 and 1732). As discussed above, operator networks mustexpand to meet the increase in user demand, support the array of newservices and provide fast, reliable communications. As the operatornetworks grow, more DCR components must be deployed in each DCR system.To support scalability, the various embodiments provide scalable DCRsystems capable of partitioning resources (e.g., logically groupingresources physically located on different DCRs and/or included indifferent DCR pairs) and storing information across the network. In anembodiment, the partitioning of resources may include performingpartitioning or domaining operations.

FIG. 17A illustrates example logical components that may be included ina scalable DCR system 1700 configured to maintain session stateinformation across partitions. The DCR system 1700 may include a firstDCR pair 1702 and a second DCR pair 1704. Each DCR pair 1702, 1704 maybe similar to the DCR pair 1602 described above with reference to FIG.16. For example, each DCR pair 1702, 1704 may include two DCRs (e.g.,DCRs 1-2, 3-4) 1706, 1708, 1710, 1712, each DCR having a DCR core 1714,1716, 1718, 1720 and a memory 1722, 1724, 1726, 1728. Each of the DCRs1706, 1708, 1710, 1712 within the first and second DCR pairs 1702, 1704may also be connected to each other by a communications link 1721, 1725and the DCR cores 1714, 1716, 1718, 1720 may be configured to replicatethe information stored in the primary memory (e.g., first memory 1722,third memory 1726) to the secondary memory (e.g., second memory 1724,fourth memory 1728). The first DCR pair 1702 may be connected to thesecond DCR pair 1704 via a communications link 1750. The first andsecond memories 1722, 1724 may be logically grouped together into afirst memory group (i.e., the first partition 1730), and the third andfourth memories 1726, 1728 may be grouped together into a second memorygroup (i.e., the second partition 1732).

This architecture enables a greater level of redundancy and enablesgraceful failover operations in the event of failure of any onecomponent. This is revealed by the information flows illustrated inFIGS. 17B and 17C.

FIG. 17B illustrates example DCR information flows in the DCR system1700 in receiving messages from a source node 902 a. Source node 902 amay be configured to communicate with a particular DCR core as theprimary DCR, and configured with a backup address to a secondary DCRcore. Under normal circumstances, each source node will communicate withits primary DCR core. However, in the event that the primary DCR core isunavailable or does not respond to messages, the source node may begincommunicating with its secondary DCR core. This is illustrated in FIG.17 B by the source node 902 a sending a signaling message to the firstDCR core (DCR-1 Core) 1714 (illustrated with the solid arrow) whilemaintaining an address for a secondary DCR core (DCR-2 Core) 1716(illustrated with the dotted arrow). While FIG. 17 B shows the secondaryDCR core being positioned within the same DCR pair 1702, the primary andsecondary DCR cores for any particular source node need not be withinthe same DCR pair, and may be located in other pairs (e.g., thesecondary DCR core could be located in DCR pair 2 1704). Provisioningsource nodes with primary and secondary DCR addresses is similar to theconfigurations discussed above with reference to FIGS. 15B, 15C and 16.In processing messages received from the source node 902 a andperforming DCR operations, the first DCR core 1714 storing sessioninformation within a primary memory, which may not be in the same DCRpair. Further, each DCR core may store session data in any one of theprimary or secondary memories within the server. This may be implementedin a manner that spreads session data from all of the DCR cores amongall of the primary memories in a semi-random manner By distributing DCRcore assignment and primary and secondary memory correlations acrossseveral DCR pairs within a given server installation may improvereliability and guard against systematic failures.

In an embodiment, the first DCR core 1714 may determine the particularprimary memory or memory group for saving session data associated with aparticular source node or even for a particular session by performing anaddress assignment operation. Thus, in the illustrated example ofmessages being received from source node 902 a, the primary DCR core1714 may perform an assignment operation on an address or sessionidentifier portion of the received message to determine that associatedsession data should be stored in the second memory partition 1732. Usingthis addressing information, the primary DCR core 1714 stores thesession information in the primary memory 1726 of the second memorypartition 1732. As discussed above, the session data may be storedwithin the memory partition in the primary memory 1726, which may thenbe replicated in the secondary memory 1728. While not shown in thisfigure, when the primary DCR core 1714 receives messages associated witha different session, performing the address assignment operation mayresult in the session data being stored in memory partition 1 1730.

The address assignment function implemented on the primary DCR core 1714may also be implemented on the secondary DCR core 1716, or on all theDCR cores within the network. This enables another DCR core (e.g., thesecondary core 1716) to access session data (e.g., data stored in memory1726) in the event that the source node 902 a begins sending it messagesrelated to a session originally managed by the primary DCR core 1714.This also enables another DCR core (e.g., the secondary core 1716) toaccess session data (e.g., data stored in memory 1726) in the event thata different source node references the same session as source node 902 abegins sending it messages. Thus, by applying the same function toinformation contained in a portion of messages received from the sourcenode 902 a, the secondary DCR core 1716 may obtain the memory partitionstoring the associated session data without requiring any communicationof memory addressing from the primary DCR core beforehand. Thisfunctionality enables the DCR core to resolve the Rx-Gx correlationproblem that can arise when the source notes are the AF and the PCEF,for example.

FIG. 17C illustrates a message flow that may occur in the event that theprimary memory 1726 within the second partition 1732 fails. As discussedabove, the memory contents of the primary memory 1726 may be replicatedto the secondary memory 1728 of the same partition. Thus, in anembodiment, memory accesses and storage communications from the primaryDCR core 1714 directed to the memory partition 1732 may be serviced bythe secondary memory 1728.

It should be appreciated that secondary DCR core assignments need not befully redundant. Instead, each DCR core may serve as a primary DCR for anumber of source nodes and as the secondary DCR for another group ofsource nodes. By distributing session data among memory partitions basedupon an addressing function which uses information from receivedmessages as the input, load-balancing and memory allocation can beaccomplished autonomously in a manner which can avoid systematic failurewhile eliminating the need to share addressing information among thevarious DCR cores.

In the various embodiments, the DCR may be configured to divide (or“fork”) a single request message (e.g., create a full or partialduplicate of the message, create child messages, etc.) that is destinedfor a single destination into multiple messages addressed to multipledestinations. As part of this message forking process, the dynamiccontext router may generate one or more child messages from the originalmessage being forked (i.e., the parent message). Each resulting message(i.e., child message) may be equal to the original message, a subset ofthe original message, or contain additional information not contained bythe original message.

FIG. 18 illustrates example logical components and data flows in adynamic context router system 1800 configured to enable a single“request” message, as well as a corresponding “response” message, to beforked at the application level and distributed to one or moreadditional nodes in accordance with an embodiment. In the illustratedexample, the dynamic context router 1804 communicates with a source peer1802, a destination peer 1806, a first network node (Node 1) 1808, and asecond network node (Node 2) 1810, each of which may be any of logicalnetwork components described above (e.g., PCEF, PCRF, OFCS, OCS, SPR,AF, etc.). The dynamic context router 1804 may receive (e.g., via dataflow 1812) a request message from the source peer 1802 and performoperations to identify an appropriate destination peer 1806 to which themessage is to be sent. The dynamic context router 1804 may send therequest message (e.g., via data flow 1814 a) to the identifieddestination peer 1806, send a duplicate of the request message (e.g.,via data flow 1814 b) to the first network node 1808, and send (e.g.,via data flow 1814 c) a new message containing values from the requestmessage to the second network node 1810. The dynamic context router 1804may receive (e.g., via data flow 1816) a response message from thedestination peer 1806 and determine the appropriate source node to whichthe response message is to be sent (e.g., source peer 1802). The dynamiccontext router may send the response message (e.g., via data flow 1818a) to the identified source node (i.e., source peer 1802) and send aduplicate of the response message (e.g., via data flow 1818 b) to thefirst network node 1808.

In an embodiment, the dynamic context router may be configured todiscard responses to forked messages. For example, in suchconfigurations, if the first network node (Node 1) 1808 generates aresponse to a request message sent via data flow 1814 b, the dynamiccontext router may choose to not to send this message back to the sourcepeer. In an embodiment, the dynamic context router may use informationfrom the message (e.g., to update a cache that may be later utilized tomake future routing decisions) before the message is discarded. In thismanner, the first network node 1808 may be an existing network node thatdoes not need to be informed that it has received a forked message (asopposed to a standard message). In an embodiment, such configurationsmay be used to perform operations for “hunting in parallel,” in which arequest may be sent to three candidate nodes, for example, and the firstnode to respond is used for further requests, while the two slowerresponses may be discarded.

When a parent message is forked into one or more child messages, eachchild message may be generated via any protocol/application/formatsupported by the dynamic context router. Each child message may be inthe same format/protocol as the parent message, or in a differentformat/protocol than the parent. Multiple child messages may begenerated from each parent. Each message may be sent to multipledestinations independent of the destinations of the other child orparent messages. Application level information from within receivedmessages and/or contextual information (which may be obtained from oneor more of the methods described above) may be used to determine whichmessages should be forked and which destination the forked messages areto be sent.

By forking request messages (as well as corresponding response messages)at the application level for distribution to additional nodes, thedynamic context router functions not only as an application-levelrouter, but also as a source node capable of generating messages basedon the content of the messages being routed. The forked messages (i.e.,child messages) may be used, for example, by other network components tocollect information about the type and content of messages beingcommunicated. The dynamic context router's ability to generate newmessages (via forking) in addition performing application-level routingoperations allows the DCR system to provide operator networks with alevel of functionality not typically provided by, or expected from,intermediate network nodes (e.g., application-level routers).

FIG. 19 illustrates a fork-routing method 1900 that may be performed bythe dynamic context router in accordance with an embodiment. In step1902, the dynamic context router may receive a first message from thesource component. In step 1904, the dynamic context router may useapplication-level information obtained from the message to determinewhich messages should be forked, and to which destination networkcomponents each of the messages are to be sent. In step 1906, thedynamic context router may use contextual information to furtherdetermine which messages should be forked and to further identifydestination network components to which the messages are to be sent. Instep 1908, the dynamic context router may fork or duplicate a singlemessage destined for a single destination into multiple forked messagesbased on the application level and/or contextual information. In step1910, the dynamic context router may send the original message to theappropriate identified destination. In step 1912, the dynamic contextrouter may send each of the forked messages to their respectiveidentified destinations.

In an embodiment, the dynamic context router may support thecommunication of messages between network components implementingdifferent flavors of the same application/protocol/message format byadding extra attribute-value pairs (AVPs) into received messages,dropping AVPs from received messages, or both. In an embodiment, thedynamic context router may maintain references to specific dictionarydatabases for applications supported by each of the network componentswith which the dynamic context router communicates. The dynamic contextrouter may communicate with the referenced dictionaries to determinewhich AVPs are to be added into the message and/or which AVP are to beremoved from the message. In this manner, the dynamic context router maysupport multiple flavors of the same application/protocol/message formateven when the specific flavors cannot be ascertained from the type orcontents of the message being communicated (e.g., the message beingcommunicated is a Diameter message, which does not include suchinformation).

In an embodiment, the dynamic context router may modify messages suchthat they can be received and processed by the receiving networkcomponent and/or without causing the receiving network component to sendan error message. In an embodiment, the dynamic context router mayconvert the messages into the specific flavors required by networkcomponents with which it communicates.

FIG. 20 illustrates logical components and interfaces in an exampledynamic context router system (DCR system) 2000 configured to facilitatethe communication of signaling messages between Diameter peers 2004. TheDCR system 2000 may include a DCR core 2002 having a Diameter protocollibrary module 2006, a dynamic context router dispatcher module 2008 anda message handler module 2010. The message handler module 2010 mayinclude a request handler module 2012, a response module 2014, and afailover handler module 2016, each of which may be a pipeline, which arediscussed in more detail further below.

In the illustrated example of FIG. 20, the DCR core 2002 includes anumber of interfaces 1-11 that facilitate communications between themodules (e.g., library module 2006, dispatcher module 2008, messagehandler module 2010, etc.) and with external resources, such as sessionstores 2020, external lookup databases 2022, user defined caches 2024,routing configuration data-stores 2026, databases storing peer topology,realm routing and application information 2028, and peer configurationdata-stores 2030. For example, the DCR core 2002 may receive DCRDiameter configuration information over interface 8, initialize aDiameter protocol library by specifying application support overinterface 5, and register any call-backs required for the Diameterprotocol library to DCR notification interface (i.e., interface 2). Eachof the interfaces 1-11 are discussed in more detail below.

The DCR core 2002 interacts with the Diameter Peers 2004 over interface1, which may be used to perform base protocol interactions (e.g.,performing capabilities exchanges, watchdog exchanges, etc.); maintainstate information for each configured peer; send and receive Diameterapplication messages to and from each peer; maintain a transaction queueof unanswered messages sent to each peer; match responses received withentries in the transaction queues; handle redirect responses receivedfrom peers; maintain redirect caches; and perform other similaroperations.

The Diameter protocol library module 2006 may communicate with the DCRdispatcher module 2008 and the message handler module 2010 overinterface 2, which may be used to pass Diameter messages (requests orresponses) to the DCR message handler module 2010 for processing; passnotifications of any peer transport failures to the DCR dispatchermodule 2008; pass all outstanding messages for a failed peer to the DCRdispatcher module 2008 in Diameter failover situations (so that analternative destination can be chosen); periodically pass information onthe sizes of peer transaction queues to the DCR dispatcher module 2008to enable it to make informed load balancing decisions; and performother similar operations. In an embodiment, the DCR dispatcher module2008 may receive notifications about the state of the Diameter peers2004 from the Diameter protocol library module 2006 over interface 2,and manage such notifications accordingly. In an embodiment, themanagement of notifications may include storing state information in alocal peer topology configuration data-store.

The DCR dispatcher module 2008 may send communications to messagehandling modules/pipelines (e.g., request handler pipeline 2012, etc.)over interface 3. For example, the DCR dispatcher module 2008 maydispatch messages (both requests and responses) received from theDiameter library module 2006 to the request handler pipeline module 2012over interface 3.

The DCR dispatcher module 2008 may receive messages from the messagehandler module 2010 over interface 4 and perform operations that assistin the identification of a suitable Diameter peer destination for thereceived messages. These operations may include: converting non-specificdomain destinations populated by routing logic into specific destinationhosts using the DCR dispatcher's 2008 knowledge of the peer topology(which may be loaded from interface 8) and each peer's availability; andselecting a specific destination based on failover and load balancingconfiguration information embedded in the peer topology definition.

The DCR dispatcher module 2008 may communicate with the Diameterprotocol library module 2006 over interface 5, which may be used to:forward a Diameter message to a nominated destination-host; generate aDiameter response to the originating diameter node (e.g., instead offorwarding to another Diameter node); generate a redirect response tothe originating diameter node; and perform other similar operations.Interface 5 may also be used by the DCR core 2002 to initialize aDiameter protocol library (e.g., by specifying application support).

The Diameter protocol library 2006 may include system libraries (e.g.,libdbprotocol.so, libdbparser.so, etc.) as well other information thatmay be used to implement base diameter protocol functionality.Information retrieved from the Diameter protocol library 2006 may alsobe used to: perform capabilities exchanges with each configured peer(which may be loaded via interface 9); maintain connectivity usingdevice watchdogs; provide an application programming interface (API)that allows the DCR core 2002 to send and receive messages from otherDiameter nodes; and provide a notification interface so that the DCRcore 2002 can be made aware of important Diameter events.

The message handler modules 2010 and the DCR dispatcher module 2008 maycommunicate with a session store 2020 via interface 6. The DCR core 2002may receive routing configuration information over interface 7.

The DCR core 2002 may receive DCR Diameter configuration informationover interface 8. The DCR Diameter configuration information may includea DCR realm based routing table and a topology tree that organizes theDiameter peers 2004 into a topology that may be used to derive loadbalancing and failover rules.

In an embodiment, the routing configuration information and logic may bedecoupled from other aspects related to Diameter connectivity. Thisallows the DCR core 2002 to support failover and load balancingoperations across all of the configured peers, while at the same time,not cluttering the routing logic with all of the peer and connectivityknowledge.

In an embodiment, the DCR routing configuration information may onlyinclude information for choosing an appropriate destination domain. Forexample, the DCR may be configured such that a telecommunicationsoperator with a requirement to route messages to one of two data centersaccording to some business rules can define domains representing thepossible destinations.

The DCR core 2002 may receive peer configuration information overinterface 9, which may be used to load configured peers. The DCR core2002 may send data requests to user defined caches via interface 10, andto external lookup engines/databases via interface 11.

As mentioned above, the DCR system may arrange network elements into alogical tree topology. The base Diameter library (on top of whichmessages processed by the DCR system may be built) maintains the peerconfiguration as a simple unstructured list. In an embodiment, the DCRsystem may, through configuration, arrange the elements of the baseDiameter library's peer configuration list into a logical tree topologyreflecting: at the top level, the high level routing domains (e.g.,destinations chosen by routing logic); within a domain, a prioritizedlist of peer groups for availability purposes; and within a peer group,an unordered list of peers for load balancing purposes. This topologyarrangement enables the DCR dispatcher 2008 to be given a high leveldestination domain and to route messages to specific peers by applyingfailover and load balancing rules. This also enables components whichload the topology configuration at run time to be informed of peeravailability.

In an embodiment, the topology arrangement may include at least onedomain in a DCR deployment, at least one peer-group per domain, and atleast one peer per peer-group. Peer groups within a domain may beprioritized, such that routing within a domain may be directed to thehighest priority peer group that is available. Peer groups may specifyhow many peer failures can be tolerated before the peer group is to beconsidered unavailable. Peer groups may also specify the load balancingalgorithms (e.g., round robin, weighted round robin, least outstandingmessages, etc.) that are to be used when routing messages to the peergroup's constituent peers.

In an embodiment, the DCR system may be configured to filter messagesbased on user defined criteria. This filtering may be performed at thebeginning, middle, or end of the request processing operations. In anembodiment, filtering may be performed after the request processingoperations to maximize the data available for use by the filteringoperations. In an embodiment, the outcome from the filter process may bea Boolean value, which may be made available to the DCR dispatcher 2008,which may generate either an error response (if the message is to befiltered) or route the message to the destination node (message is notfiltered).

In an embodiment, the dynamic context router system may be configured toappend information, such as domain failover information, to the messagesin the transaction queue. This enables the dynamic context router tosubsequently take actions using this additional information which wouldotherwise not be possible. The DCR system may also store a destinationdomain in the transaction queue. In an embodiment, if a failover islater initiated, the DCR system may choose an alternative destinationhost based on the originally chosen destination domain.

In an embodiment, the DCR system may be configured to process messagesby decoding a received message into an internal representation of themessage (e.g., a structured message format proprietary to the DCRsystem), and passing it to a routing logic module/pipeline responsiblefor performing the routing operations. In an embodiment, the internalrepresentation may be an AVS.

In an embodiment, the DCR system may implement a fixed pipeline model(e.g., a model in which each module includes a number of optional stepsfor performing a\ specific set of tasks) to control the processing ofthe message. For example, Diameter request messages received by the DCRsystem may be processed by a request pipeline, which may make routingdecisions and/or manipulate the message using a discrete number ofconfigurable steps.

As discussed above with reference to FIG. 20, each of the messagehandling modules (e.g., request handler module 2012, response module2014, failover handler module 2016, etc.) may be a pipeline, and thevarious DCR message handling operations may be managed by a separatepipeline depending on the type of message or type of operation (e.g.,requests, responses, failovers, etc.). For example, messages originatingfrom the Diameter protocol library module 2006 may be passed (e.g., viathe DCR dispatcher module 2008, etc.) to the appropriatepipelines/modules within the message handling module 2010 responsiblefor processing the message. Each pipeline may be configured inaccordance with user preferences, network requirements, deploymentenvironment and/or user requirements. Each pipeline may also beconfigured on a “per message type” and/or “per application” bases.

In the various embodiments, each pipeline may be minimally configured orextensively configured. For example, a pipeline may be minimallyconfigured to handle situations where the Diameter realm based routingtable provides all of the information necessary to route a message, orextensively configured to handle situations requiring custom processinginvolving lookups and routing logic.

Each of the message handling pipelines/modules may include a number ofsub-modules (steps) that provide a set of highly customizable functions.For example, each module/step may be configured to perform a specificset of operations such as: interacting with the default session store(e.g., when session state only needs to store a destination choice);interacting with a user defined session store (e.g., for more complexsession store operations); augmenting the incoming message by performingexternal and internal lookups (e.g., via interfaces 10 and 11 of FIG.20) using keys from the incoming message or from the results of otherlookups; examining the contents of augmented message to choose one ormore destination domains or to perform message destination huntingoperations; preparing message to be routed by modifying, adding orremoving AVPs from one or more messages; filtering messages via a userdefined white-list or black-list (e.g., refusing to route the message),etc. Each sub-module (step) may have a specific set of permissions thatlimit the allowable operations available to that step, which may bebased on a number of configurable factors (e.g., type of modulerequesting the operation, deployment environment, network conditions,etc.).

In an embodiment, each pipeline may be a fixed message handling pipelinethat aids the management of routing decisions and/or messagemanipulation operations.

In an embodiment, each pipeline may be configured at an applicationcommand level granularity. For example, each pipeline may be configuredfor Gx-based credit control requests.

In an embodiment, the DCR system may be configured to detect theexistence of an empty pipeline (e.g., a pipeline that is not configured,is configured to exclude all steps, etc.) and perform routing operationsusing the routing functionality of the base Diameter protocol.

In the various embodiments, the DCR system may include one or more of arequest handling pipeline, a response handling pipeline, and a failoverhandling pipeline.

FIG. 21 illustrates a request pipeline 2102 for processing Diameterrequest messages. The request pipeline 2102 may be a part of the DCRcore, which may utilize the request pipeline 2102 to make routingdecisions (e.g., locating a destination node, determining that themessage cannot be routed, etc.) and/or to manipulate messages. Therouting logic used to process the messages may be specific to thereceived message or message type. In an embodiment, the routing logicmay be dynamic and/or attached to each pipeline stage via a proprietaryDCR scripting language.

In an embodiment, each incoming request message may be passed to therequest pipeline 2102, which is then identified by application andcommand. An empty routing ticket may be constructed upon entry to thepipeline process, which is then populated with a decoded internalrepresentation of the received request message.

The request pipeline 2102 may include a number of discrete steps,stages, or modules (herein steps which may be performed in sequence as amessage passes through the pipeline 2102), with each step performing adistinct DCR operation. Each step of the pipeline may populate differentportions of the routing ticket, which may include portions for: thedecoded request message (AVS type structure); raw data (e.g., messagedata not decoded); a request action; lookup results; session state;destination domain(s); a filter decision; and redirect AVPs. In theexample illustrated in FIG. 21, the request pipeline 2102 includes arealm routing lookup step 2110, a session lookup step 2112, a gatherdata step 2114, a routing core step 2116, a prepare AVS step 2118, afilter step 2120, a dispatcher step 2122, and a session update step2124.

In the realm routing lookup step 2110, the request pipeline may performa lookup on a configured realm based routing table. The realm basedrouting table may have the same or similar characteristics as a standardDiameter routing table (as described in Diameter standards RFC 3588), ormay be a modified version of a standard Diameter routing table.

In an embodiment, the realm based routing table may include thefollowing modifications over a standard Diameter routing table: aconfiguration column containing an “Override Destination” flag, whichmay express whether the destination read from a row in the table can beoverridden; a configuration column containing an “Override Action” flag,which may express whether the action read from this row in the table canbe overridden; a “Redirect host usage” column and a “Redirect max cachetime” column, which may be used when the action is redirect and theredirect response message should populate correspondingly named AVPs; aserver column renamed to domain, which may contain the name of a DCRconfigured domain rather than a specific host (as would be the caseunder Diameter standards RFC3588).

As mentioned above, the DCR system may be configured to perform decodingoperations in multiple phases. In such configurations, the incomingrequest message may be partially decoded during the realm routing lookupstep 2110 (e.g., only the header and base protocol routing AVPs may beextracted). The entire message may or may not be fully decoded (at alater stage) depending on an outcome of the lookup operations. Forexample, if there is no match resulting from the table look, or if theaction is proxy and the destination domain is assigned, the message maybe fully decoded. On the other hand, the message may be partiallydecoded if the action is relay or redirect, and the destination domainis assigned. The DCR system may also be configured to cause the messageto be handled (e.g., routing the message, rejecting the message, etc.)at a later stage/step when there is no match on the table lookup byfully decoding the message but not setting a destination domain. In anembodiment, the outcome of the realm routing lookup step 2110 may beoverridden depending on the value of the override flags in a matchedtable row.

The session lookup step 2112 may be performed as part of establishingsession stickiness. In the session lookup step 2112, the DCR system maydetermine if the message belongs to a known and previously routedsession. If so, the destination host and destination domain may be setin the routing ticket. In an embodiment, the session lookup step 2112may be minimally configured for applications that do not need tomaintain session state other than the routing destination. In anembodiment, the session lookup step 2112 may be more extensivelyconfigured (e.g., via a proprietary DCR language) to perform customoperations and/or to include a custom session store.

In the gather data step 2114, the DCR system may gather data upon whichrouting decisions may depend (e.g., via cache lookups, external lookups,reference data lookups, etc.), configure the execution of the requiredlookups, reference the predefined lookup definitions and/or provide keysfrom any data available in the routing ticket. In an embodiment, the DCRsystem may populate a lookup results section of the routing ticket withthe results of lookups performed as part of the gather data step 2114.

In the routing core step 2116, the DCR system may make routing decisionsbased on any of the information available in the routing ticket. As partof the routing core step 2116, the DCR system may also populate thedestination domain in the routing ticket (assuming it was not alreadyset by previous stages or it is allowed to override a previously setvalue) and/or override request actions (e.g., proxy, relay, redirect,unset, etc.) populated in the realm table (e.g., via the realm tablelookup step 2110 discussed above). In an embodiment, when the requestaction is “unset,” as part of the routing core step 2116, the DCR systemmay choose a method of delivery (e.g., proxy, relay or redirect) inaddition to making a routing decision. In an embodiment, routingdecisions made in the routing core step 2116 may be configured via aproprietary DCR language to perform custom logic/operations.

In the prepare AVS step 2118, the DCR system may make modifications tothe message before it is sent. These modifications may include theaddition of new AVPs, the modification of existing AVPs or the removalof AVPs. In an embodiment, the prepare AVS step 2118 may be limited tomodifying the message within the routing ticket. In an embodiment,details of how the messages are modified in the prepare AVS step 2118may be configured via a proprietary DCR language.

In the filter step 2120, the DCR system may filter messages based onuser defined criteria. In an embodiment, the user-defined criteria maybe specified via a proprietary DCR language.

In the dispatcher step 2122, the DCR system may choose a specific host.If a destination host and a destination domain are not specified byearlier stages in the pipeline 2102 (i.e., no host, no domain), an errorresponse message may be sent to the network node originating the message(e.g., the source node). If a destination host is provided but there isno destination domain (i.e., provided host, no domain), the message maybe routed to the specified destination host, and an error response maybe sent to the originator of the message if the host is unavailable. Ifa destination host and a destination domain are both provided (i.e.,provided host, provided domain), the message may be routed to theprovided destination host, and an alternative destination host may beattempted if the specified one is unavailable. If no destination host isprovided (i.e., no host, provided domain), an appropriate destinationhost may be chosen from the specified destination domain (e.g., viaperforming failover and load balancing operations), and an errorresponse may be sent to the originator of the message if there are noavailable hosts within the domain.

As discussed above, messages handling operations may be facilitated bypassing a routing ticket along various stages of a message handlingpipeline. The dispatcher step 2122 may receive the routing ticketpopulated with: an action (e.g., Proxy, Relay, Redirect, etc.); anon-specific list of destination domains or a specific destination-host(if the message arrived at the DCR with this already set); the messageto be sent (which may be a modified message); redirect related AVPs(which may be specified if the action is redirect); and/or a decision(e.g., yes, no) from the filter stage of the request pipeline.

In an embodiment, in the dispatcher step 2122, the DCR system mayexamine the routing ticket and perform operations (e.g., make calls tothe Diameter protocol library) based on the contents of the examinedmessage.

In an embodiment, in the dispatcher step 2122, the DCR system maygenerate a response message to be sent back to the originating peer withthe Result-Code AVP set to “DIAMETER_UNABLE_TO_COMPLY” if the messagefiltering flag is set.

In an embodiment, in the dispatcher step 2122, the DCR system may selecta peer from the specified domain if the action is proxy or relay, thedestination-host is not specified and the destination-domain isspecified. The highest priority available peer group from the domain maybe chosen and a peer from within the chosen peer group may be chosen byperforming a load balancing algorithm. If there are no available peergroups, an error response may be generated with Result-Code set to“DIAMETER_UNABLE_TO_DELIVER”.

In an embodiment, in the dispatcher step 2122, the DCR system may routethe message to a specified destination-host if the action is proxy orrelay, the destination-host is specified and the Destination-Domain isnot specified (e.g., when the destination-host is provided by theincoming message or else populated by session stickiness processing). Amessage may be sent to a peer regardless of the state of its containingpeer group (e.g., when a parent peer group is unavailable but therequired child peer is available). If the specified peer is unavailablethen an error may be returned to the originator specifying a Result-Codeset to “DIAMETER_UNABLE_TO_DELIVER”.

In an embodiment, in the dispatcher step 2122, the DCR system may send amessage to a specified destination-host if the action is proxy or relay,the destination-host is specified, and the destination-realm isspecified. If the destination-host it is not available, the dispatchermay choose an alternative destination-host from the nominateddestination-realm.

In an embodiment, in the dispatcher step 2122, the DCR system may send aredirect response to the originating node specifying the accompanyingredirect related AVPs, Redirect-Cache-Usage and Redirect-Max-Cache-Timeif the if the action is Redirect.

In an embodiment, in the dispatcher step 2122, the DCR system mayperform message manipulation operations (e.g., changing theend-to-end-id, Route-Record and Origin-Host AVPs) if the message is tobe routed onward and the topology hiding option is configured for themessage.

The dispatcher step 2122 may receive multiple possible destinationdomains a part of hunting operations. When the dispatcher is required toroute a message and it detects that destination domain is actually alist of possible destinations, the dispatcher may strip the firstdestination from the list and use it as the destination domain. The restof the list may be stored in the transaction queue of the Diameterprotocol library module and used by the response handling pipeline todetermine the next destination that is to be tried if a response messageindicates a failure.

In an embodiment, if a destination host and a destination domain are notspecified by earlier stages in the pipeline 2102 (i.e., no host, nodomain), an error response message may be sent to the network nodeoriginating the message (e.g., the source node). If a destination hostis provided but there is no destination domain (i.e., provided host, nodomain), the message may be routed to the specified destination host,and an error response may be sent to the originator of the message ifthe host is unavailable. If a destination host and a destination domainare both provided (i.e., provided host, provided domain), the messagemay be routed to the provided destination host, and an alternativedestination host may be attempted if the specified one is unavailable.If no destination host is provided (i.e., no host, provided domain), anappropriate destination host may be chosen from the specifieddestination domain (e.g., via performing failover and load balancingoperations), and an error response may be sent to the originator of themessage if there are no available hosts within the domain.

In the session update step 2124, the DCR system may update one or moresession stores by inserting new session entries, updating existingsessions and/or deleting session entries.

In an embodiment, the DCR system may be configured to process Diameterresponse messages via a response pipeline 2202, an example of which isillustrated in FIG. 22. The response pipeline 2202 may be a part of theDCR core. The response pipeline 2202 may include a number of discretesteps, stages, or modules (herein steps), each step performing adistinct DCR operation.

The DCR system may construct an empty routing ticket at an entry to thepipeline and populate the empty routing ticket with a decoded internalrepresentation of the Diameter response message, as well as with datastored with the matching original request. Each step of the pipeline maypopulate different portions of the routing ticket, which may includeportions for: the decoded response message (AVS type structure); rawdata (e.g., message data not decoded); the originally decoded requestmessage (AVS type structure); any data that was stored with the requestin the transaction queue; destination domain list; lookup results; and aresponse action (e.g., Send, Send-Next, Respond, Redirect).

In an embodiment, the response pipeline 2202 may be a subset of therequest pipeline and/or include steps that perform operations similar tothose performed by the request pipeline steps. In the illustratedexample of FIG. 22, the response pipeline 2202 includes a gather datastep 2210, a routing core step 2212, a prepare AVS step 2214 and adispatcher step 2216. In the gather data step 2210, the DCR system maygather data upon which routing decisions may depend (e.g., via cachelookups, external lookups, reference data lookups, etc.). The DCR systemmay also configure the execution of the required lookups, reference thepredefined lookup definitions and provide keys from any data availablein the routing ticket. In the routing core step 2212, the DCR system maymake routing decisions based on any of the information available in therouting ticket. In the prepare AVS step 2214, the DCR system may makemodifications to the message before it is sent (e.g., adding new AVPs,modifying existing AVPs or removing AVPs). In the dispatcher step 2216,the DCR system may choose a specific host.

In an embodiment, the DCR system may be configured to accommodatecomponent, system node and partial network failures, as well as discretemessage delivery failures, in failover operations using a failoverpipeline 2302, an example of which is illustrated in FIG. 23. Thefailover pipeline 2302 may be a part of the DCR core. The failoverpipeline 2302 may include a number of discrete steps, stages, or modules(herein steps), each step performing a distinct DCR operation. In theillustrated example of FIG. 23, the failover pipeline 2302 includes adispatcher step 2310 and a session update step 2312.

For example, in an embodiment, the DCR system may detect a transportfailure and initiate Diameter failover procedures by sending theoutstanding messages destined for the failed peer to the DCR failoverpipeline 2302 for reprocessing. The DCR failover pipeline 2302 maychoose an alternative destination for the message (e.g., based on theoriginal destination host and/or original destination domain) in thedispatcher step 2310, and update the session store with the updateddestination in session update step 2312. If the DCR system determinesthat the message cannot be re-routed, the DCR system may generate aresponse message to be sent to the requesting node. If the DCR systemdetermines that the message can be re-routed, the message is re-routedto the alternative destination determined in the dispatcher step 2310.In the session update step 2312, the session store may be updated withnew destination information.

In an embodiment, the DCR system (e.g., in the DCR failover pipeline2302) may be configured to determine when it is not possible to route toan alternative destination by determining if the message was originallysent to a fixed destination to which no alternative destination isacceptable (e.g., the message requires a specific destination node)and/or by determining if all acceptable alternative peers areunavailable.

In an embodiment, the DCR system may perform application leveloperations in response to receiving a redirect message. As discussedabove, the DCR system may receive redirect response messages fromnetwork peers, which may be processed without performingapplication-level operations in response to receiving the message. In anembodiment, the DCR system may be configured to performapplication-level operations (e.g., update an application level cache inorder to avoid unnecessary or incorrect routing of future messages) inresponse to receiving a redirect message. The DCR system may beconfigured to perform the application level redirect operations using aredirect pipeline 2402, an example of which is illustrated in FIG. 24.The redirect pipeline 2402 may be a part of the DCR core. The redirectpipeline 2402 may include a number of discrete steps, stages, or modules(herein steps), each step performing a distinct DCR operation. Forexample, the redirect pipeline may include a redirect step 2410 and adispatcher step 2412.

In the various embodiments, the DCR system may create a cache with anidentity, a configured key and an AVS for storage.

In the various embodiments, reference data may be configured by:defining a named reference data lookup by configuring the structure ofthe stored data; populating the reference data by importing a structuredfile, such as a file containing comma separated values; and/or allowingincremental updates to the reference data by importing file updates.Reference data may be non-volatile and persist across restarts.

As mentioned above, the DCR system may perform operations to establishsession stickiness. For example, each time a session initializationmessage is routed though the DCR, the DCR system may make adetermination as to whether session stickiness is required, and addsession information to a session store if it is determined that sessionstickiness is required. Likewise, when the DCR system receives a sessionupdate message or a terminate message, the DCR system may update orremove entries from the session stores, respectively. In an embodiment,the various session sticky behaviors may be implemented in two separateparts of the DCR request processing pipeline. In an embodiment, the DCRsystem include a session store that uses known AVPs as keys and storesonly routing information.

In an embodiment, the DCR system may perform topology hiding operations.Since Diameter is an end to end protocol, when Diameter clientapplications interact with server applications, the clients, throughinspection of base routing AVPs, can learn about the multiplicity andaddresses of server nodes, as well as the hops involved in reachingthose servers. In some cases (e.g., where inter-PLMN routing of Diametermessages is performed) it is desirable to hide the server locations fromclient applications. In an embodiment, the DCR system may operate as ajoint server and client Diameter node. In this manner, intermediatenodes cannot determine the true destination of a Diameter messagebecause the information contained within the message will list the DCRsystem as the source/destination.

In an embodiment, the DCR system may perform topology hiding operationsvia AVP manipulation in order to make messages being routed by the DCRappear to originate from the DCR. In an embodiment, the manipulation ofthe AVPs for topology hiding may be performed within a dispatcher moduleor step (e.g., dispatcher step 2122) in a message processing pipeline.The dispatcher's topology configuration may include the ability toindicate if topology hiding should be applied on a per domain basis. Forexample, in a request processing pipeline (e.g., request pipeline 2102)the dispatcher (e.g., dispatcher step 2122) may receive a routing ticketwith a destination domain(s) and a destination-host. If a selecteddestination domain requires topology hiding, then the dispatcher maymodify the relevant AVPs such as the Origin-Host AVP and theRoute-Record AVP to contain the DCR Diameter identity, and modify theEnd-to-End-Id AVP for the onward hop. In this case, the dispatcher(e.g., dispatcher step 2216) in the response processing pipeline (e.g.,response pipeline 2202) may subsequently need to make equivalenttopology hiding modifications. Topology hiding may also be applied inthe same manner if it is required by the origin domain.

As discussed above, each of the request handling pipeline 2102, responsehandling pipeline 2202, failover handling pipeline 2302, and redirectpipeline 2402 may include a dispatcher step or module (hereindispatcher) responsible for mapping the destination domain decisions tospecific destination hosts (with reference to the peer topology). In anembodiment, the dispatcher may map messages arriving from Diameter peersto the correct message handler, and handle notifications from theDiameter library about peer state changes and transaction queue sizes,such that the DCR system can make informed routing decisions.

In an embodiment, the DCR system may be configured to notify thedispatcher of peer state changes (e.g., via the Diameter library), whichmay be used by the dispatcher to make informed routing decisions bycombining the peer topology and peer state.

In an embodiment, the dispatcher may translate a non-specific domaindestination into a specific peer for routing by choosing the highestpriority available peer group in the specified domain, and choosing apeer from the chosen peer group based on the configured load balancingalgorithm.

The various embodiments may be implemented on any of a variety ofcommercially available server devices, such as the server 2500illustrated in FIG. 25. Such a server 2500 typically includes aprocessor 2501 coupled to volatile memory 2502 and a large capacitynonvolatile memory, such as a disk drive 2503. The server 2500 may alsoinclude a floppy disc drive, compact disc (CD) or DVD disc drive 2506coupled to the processor 2501. The server 2500 may also include networkaccess ports 2504 coupled to the processor 2501 for establishing dataconnections with a network 2505, such as a local area network coupled toother operator network computers and servers.

The processor 2501 may be any programmable microprocessor, microcomputeror multiple processor chip or chips that can be configured by softwareinstructions (applications) to perform a variety of functions, includingthe functions of the various embodiments described below. Multipleprocessors 2501 may be provided, such as one processor dedicated towireless communication functions and one processor dedicated to runningother applications. Typically, software applications may be stored inthe internal memory 2502, 2503 before they are accessed and loaded intothe processor 2501. The processor 2501 may include internal memorysufficient to store the application software instructions.

The foregoing method descriptions and the process flow diagrams areprovided merely as illustrative examples and are not intended to requireor imply that the steps of the various embodiments must be performed inthe order presented. As will be appreciated by one of skill in the artthe order of steps in the foregoing embodiments maybe performed in anyorder. Words such as “thereafter,” “then,” “next,” etc. are not intendedto limit the order of the steps; these words are simply used to guidethe reader through the description of the methods. Further, anyreference to claim elements in the singular, for example, using thearticles “a,” “an” or “the” is not to be construed as limiting theelement to the singular.

The various illustrative logical blocks, modules, circuits, andalgorithm steps described in connection with the embodiments disclosedherein may be implemented as electronic hardware, computer software, orcombinations of both. To clearly illustrate this interchangeability ofhardware and software, various illustrative components, blocks, modules,circuits, and steps have been described above generally in terms oftheir functionality. Whether such functionality is implemented ashardware or software depends upon the particular application and designconstraints imposed on the overall system. Skilled artisans mayimplement the described functionality in varying ways for eachparticular application, but such implementation decisions should not beinterpreted as causing a departure from the scope of the presentinvention.

The hardware used to implement the various illustrative logics, logicalblocks, modules, and circuits described in connection with the aspectsdisclosed herein may be implemented or performed with a general purposeprocessor, a digital signal processor (DSP), an application specificintegrated circuit (ASIC), a field programmable gate array (FPGA) orother programmable logic device, discrete gate or transistor logic,discrete hardware components, or any combination thereof designed toperform the functions described herein. A general-purpose processor maybe a microprocessor, but, in the alternative, the processor may be anyconventional processor, controller, microcontroller, or state machine Aprocessor may also be implemented as a combination of computing devices,e.g., a combination of a DSP and a microprocessor, a plurality ofmicroprocessors, one or more microprocessors in conjunction with a DSPcore, or any other such configuration. Alternatively, some steps ormethods may be performed by circuitry that is specific to a givenfunction.

In one or more exemplary aspects, the functions described may beimplemented in hardware, software, firmware, or any combination thereof.If implemented in software, the functions may be stored on ortransmitted over as one or more instructions or code on acomputer-readable medium. The steps of a method or algorithm disclosedherein may be embodied in a processor-executable software module whichmay reside on a tangible, non-transitory computer-readable storagemedium. Tangible, non-transitory computer-readable storage media may beany available media that may be accessed by a computer. By way ofexample, and not limitation, such as, non-transitory computer-readablemedia may comprise RAM, ROM, EEPROM, CD-ROM or other optical diskstorage, magnetic disk storage or other magnetic storage devices, or anyother medium that may be used to store desired program code in the formof instructions or data structures and that may be accessed by acomputer. Disk and disc, as used herein, includes compact disc (CD),laser disc, optical disc, digital versatile disc (DVD), floppy disk, andblu-ray disc where disks usually reproduce data magnetically, whilediscs reproduce data optically with lasers. Combinations of the aboveshould also be included within the scope of non-transitorycomputer-readable media. Additionally, the operations of a method oralgorithm may reside as one or any combination or set of codes and/orinstructions on a tangible, non-transitory machine readable mediumand/or computer-readable medium, which may be incorporated into acomputer program product.

The preceding description of the disclosed embodiments is provided toenable any person skilled in the art to make or use the presentinvention. Various modifications to these embodiments will be readilyapparent to those skilled in the art, and the generic principles definedherein may be applied to other embodiments without departing from thespirit or scope of the invention. Thus, the present invention is notintended to be limited to the embodiments shown herein but is to beaccorded the widest scope consistent with the following claims and theprinciples and novel features disclosed herein.

1-15. (canceled)
 16. A method of communicating signaling information ina telecommunications signaling network, comprising: receiving in aprocessor of a server computing device from a source component acommunication message that encodes signaling information; decoding thereceived communication message into an internal representation thatstores the signaling information included in the received communicationmessage in two or more structured information fields; using informationderived from the internal representation to determine whether messagedestination hunting operations should be performed; performingnode-selection operations to select a destination component in responseto determining that message destination hunting operations should beperformed; encoding the signaling information included in the internalrepresentation into a second communication message; and sending thesecond communication message to the selected destination component. 17.The method of claim 16, further comprising: determining whether aresponse was received from the selected destination component; andadding the selected destination component to a do-not-use list inresponse to determining that no response was received from the selecteddestination component.
 18. The method of claim 16, further comprising:receiving a response from the selected destination component;determining whether the received response is a negative response; addingthe selected destination component to a do-not-use list in response todetermining that the received response is a negative response; andstoring correlation information in memory in response to determiningthat the received response is not a negative response.
 19. The method ofclaim 16, further comprising: repeating the node-selection operations toselect a new destination component in response to determining thateither no response or a negative response was received from the selecteddestination component.
 20. The method of claim 16, wherein performingnode-selection operations to select a destination component comprisesperforming a randomization operation.
 21. The method of claim 16,wherein: using information derived from the internal representation todetermine whether message destination hunting operations should beperformed further comprises determining whether the internalrepresentation includes information relating to a subscriber; andperforming node-selection operations to select the destination componentcomprises selecting a component based on whether the component couldstore information associated with the subscriber.
 22. The method ofclaim 16, wherein: using information derived from the internalrepresentation to determine whether message destination huntingoperations should be performed further comprises determining whether theinternal representation includes information relating to a session; andperforming node-selection operations to select the destination componentcomprises selecting a component based on whether the component couldstore information associated with the session.
 23. The method of claim16, wherein: performing node-selection operations to select thedestination component comprises selecting at least two destinationcomponents; and sending the second communication message to the selecteddestination component comprises sending the second communication messageto the selected at least two destination components.
 24. The method ofclaim 16, wherein encoding the signaling information included in theinternal representation into the second communication message comprisesencoding the signaling information so that sending the secondcommunication message to the selected destination component comprisessending the selected destination component one of: a message thatincludes at least one field having a value that differs from a value ofa corresponding field in the received communication message; a messagethat includes a superset of the signaling information included thereceived communication message; and a message that includes a subset ofthe signaling information included the received communication message.25. The method of claim 16, wherein: receiving the communication messagethat encodes signaling information comprises receiving a first messagethat encodes the signaling information using a first protocol; andencoding the signaling information included in the internalrepresentation into a second communication message comprises encodingthe signaling information included in the internal representation into asecond message that encodes the signaling information using a secondprotocol that is different from the first protocol.
 26. A servercomputing device, comprising: a processor configured withprocessor-executable instructions to perform operations comprising:receiving from a source component a communication message that encodessignaling information; decoding the received communication message intoan internal representation that stores the signaling informationincluded in the received communication message in two or more structuredinformation fields; using information derived from the internalrepresentation to determine whether message destination huntingoperations should be performed; performing node-selection operations toselect a destination component in response to determining that messagedestination hunting operations should be performed; encoding thesignaling information included in the internal representation into asecond communication message; and sending the second communicationmessage to the selected destination component.
 27. The server computingdevice of claim 26, wherein the processor is configured withprocessor-executable instructions to perform operations furthercomprising: determining whether a response was received from theselected destination component; and adding the selected destinationcomponent to a do-not-use list in response to determining that noresponse was received from the selected destination component.
 28. Theserver computing device of claim 26, wherein the processor is configuredwith processor-executable instructions to perform operations furthercomprising: receiving a response from the selected destinationcomponent; determining whether the received response is a negativeresponse; adding the selected destination component to a do-not-use listin response to determining that the received response is a negativeresponse; and storing correlation information in memory in response todetermining that the received response is not a negative response. 29.The server computing device of claim 26, wherein the processor isconfigured with processor-executable instructions to perform operationsfurther comprising: repeating the node-selection operations to select anew destination component in response to determining that either noresponse or a negative response was received from the selecteddestination component.
 30. The server computing device of claim 26,wherein the processor is configured with processor-executableinstructions to perform operations such that: using information derivedfrom the internal representation to determine whether messagedestination hunting operations should be performed further comprisesdetermining whether the internal representation includes informationrelating to a subscriber; and performing node-selection operations toselect the destination component comprises selecting a component basedon whether the component could store information associated with thesubscriber.
 31. A non-transitory computer readable storage medium havingstored thereon processor-executable software instructions configured tocause a processor of a server computing device to perform operationscomprising: receiving from a source component a communication messagethat encodes signaling information; decoding the received communicationmessage into an internal representation that stores the signalinginformation included in the received communication message in two ormore structured information fields; using information derived from theinternal representation to determine whether message destination huntingoperations should be performed; performing node-selection operations toselect a destination component in response to determining that messagedestination hunting operations should be performed; encoding thesignaling information included in the internal representation into asecond communication message; and sending the second communicationmessage to the selected destination component.
 32. The non-transitorycomputer readable storage medium of claim 30, wherein the storedprocessor-executable software instructions are configured to cause themobile device processor to perform operations further comprising:determining whether a response was received from the selecteddestination component; and adding the selected destination component toa do-not-use list in response to determining that no response wasreceived from the selected destination component.
 33. The non-transitorycomputer readable storage medium of claim 30, wherein the storedprocessor-executable software instructions are configured to cause themobile device processor to perform operations further comprising:receiving a response from the selected destination component;determining whether the received response is a negative response; addingthe selected destination component to a do-not-use list in response todetermining that the received response is a negative response; andstoring correlation information in memory in response to determiningthat the received response is not a negative response.
 34. Thenon-transitory computer readable storage medium of claim 30, wherein thestored processor-executable software instructions are configured tocause the mobile device processor to perform operations furthercomprising: repeating the node-selection operations to select a newdestination component in response to determining that either no responseor a negative response was received from the selected destinationcomponent.
 35. The non-transitory computer readable storage medium ofclaim 30, wherein the stored processor-executable software instructionsare configured to cause the mobile device processor to performoperations such that: using information derived from the internalrepresentation to determine whether message destination huntingoperations should be performed further comprises determining whether theinternal representation includes information relating to a subscriber;and performing node-selection operations to select the destinationcomponent comprises selecting a component based on whether the componentcould store information associated with the subscriber.